diff --git a/CHANGELOG.md b/CHANGELOG.md
index 66e0b1d..e3bd4f3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,19 @@
 # Changelog Backuppy
 
+## [0.9] - 2021-05-10
+### Added
+- CLI-mode: It's now possible to end the program anytime with ":q" (or ESC-key) and pressing ENTER.
+- CLI-mode: Colored output on traces
+- New helper script "utils.py"
+
+### Changed
+- Code refactoring (get rid of global variables and constants, instead pass as arguments)
+
+## [0.8.1] - 2021-05-10
+### Fixed
+- CLI-mode: Show text "Programm interrupted by user." instead of error message when Ctrl+C was pressed.
+- CLI-mode: Removed obsolete trace messages
+
 ## [0.8] - 2021-05-07
 ### Added
 - GUI-mode: Introduce "Browse"-button on directory-selection dialogs
diff --git a/install.py b/install.py
index d6468be..490916b 100644
--- a/install.py
+++ b/install.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 """
 project: Backuppy
-version: 0.8
+version: 0.9
 file: install.py
 summary: python installer-script in CLI-mode
 """
@@ -9,114 +9,87 @@ summary: python installer-script in CLI-mode
 # Standard library imports
 import sys
 import os
-import time
 
 # local imports
-from languages import english
-from languages import german
+from utils import set_language, query, _print, trace
 
 # local globals
-# ----------------------
-VERSION: str = "0.8"
+VERSION: str = "0.9"
 EMAIL = "fotocoder@joschu.ch"
 EXCLUDE_FILE = "exclude.txt"
 BACKUPPY_SCRIPT = "Backuppy.sh"
-# ----------------------
-MYDIR = os.getcwd()
-EXCLUDE: bool = False
-SHELL = os.environ.get("SHELL")
-HOME = os.environ.get("HOME")
-LANG_EN = "English"
-LANG_DE = "German"
-LANGUAGE = LANG_EN
-RSYNC_CMD: str = None
 
-def set_language(language):
-    global LANGUAGE
-    LANGUAGE = language
+def main_install_cli(mydir, exclude_file):
+    language = query("welcome")
+    if not language:
+        return False, None, None
+    set_language(language)
 
-def trace(message_txt):
-    """ Print a formatted message to std out. """
-    print("[  OK  ] " + message_txt)
+    _print("languagepack")
 
-def get_lang_text(search_str: str):
-    global LANGUAGE
-    """ Returns a string from the appropriate language file. """
-    return_str: str = eval("english."  + search_str) 
-    if LANGUAGE == LANG_DE:
-        return_str = eval("german."  + search_str)
-    return return_str
+    _print("intromsg1")
 
-def main_install_cli():
-    language = input("Hello, first of all, which language do you prefer: German [DE] or English [EN]?\n> ")
-    if language.upper() == "DE":
-        set_language(LANG_DE)
-        print("Perfekt, nun ist das deutsche Sprachpaket aktiviert. Willkommen!\n")    
-    else:
-        print("Perfect, the English language package is now activated. Welcome!.\n")
-
-    time.sleep(1)
-
-    print("\n" + get_lang_text("intromsg1") + "\n")
-    time.sleep(1)
-
-    print("\n" + get_lang_text("intromsg2") + "\n")
-    time.sleep(1)
+    _print("intromsg2")
 
     # which Rsync options are available and which one you want to use
-    print(get_lang_text("rsyncopt") + "\n")
-    time.sleep(1)
+    _print("rsyncopt")
 
     # asks if you want to exclude files/directories from backup and creates an exclude file in case of Yes
-    exclude = input(get_lang_text("excludefile1") + "\n> ")
-    global EXCLUDE
-    if exclude.upper() in ("J", "Y"):
-        EXCLUDE = True
-        print(get_lang_text("excludefile2") + "\n")
+    exclude = query("excludefile1")
+    if not exclude:
+        return False, None, None
+    elif exclude.upper() in ("J", "Y"):
+        _print("excludefile2")
+        exclude = True
     else:
-        EXCLUDE = False
-        print(get_lang_text("excludefile3") + "\n")
-    time.sleep(1)
+        _print("excludefile3")
+        exclude = False
 
     # Asks for the source directory which should be saved
-    print(get_lang_text("srcdir1"))
-    time.sleep(1)
-    sourcedir = input(get_lang_text("srcdir2") + "\n> ")
+    _print("srcdir1")
+    sourcedir = query("srcdir2")
+    if not sourcedir:
+        return False, None, None
 
-    print(f"{get_lang_text('srcdir3_1')} {sourcedir} {get_lang_text('srcdir3_2')}")
-    time.sleep(1)
+    _print("srcdir3_1")
+    print(sourcedir)
+    _print("srcdir3_2")
 
     # asks for the destination directory in which the backup should be saved
-    targetdir = input(get_lang_text("targetdir1") + "\n> ")
-    print(f"{get_lang_text('targetdir2_1')} {targetdir} {get_lang_text('targetdir2_2')}")
-    time.sleep(1)
+    targetdir = query("targetdir1")
+    if not targetdir:
+        return False, None, None
+
+    _print("targetdir2_1")
+    print(targetdir)
+    _print("targetdir2_2")
 
     # collects all the information needed to execute the rsync command and creates it.
-    print(get_lang_text("collect") + "\n")
-    time.sleep(1)
-    exclude_file = os.path.join(MYDIR, EXCLUDE_FILE)
-    
-    RSYNC_CMD = f"rsync -aqp --exclude-from={exclude_file} {sourcedir} {targetdir}"
+    _print("collect")
 
-    print(f"{RSYNC_CMD}")
-    time.sleep(1)
+    rsync_cmd = f"rsync -aqp --exclude-from={os.path.join(mydir, exclude_file)} {sourcedir} {targetdir}"
+
+    print(f"{rsync_cmd}")
 
     # Outro
-    print(get_lang_text("outro1"))
-    time.sleep(2)
-    print(get_lang_text("outro2") + " " + EMAIL)
+    _print("outro1")
 
-    return True, EXCLUDE, RSYNC_CMD
+    _print("outro2")
+    print(EMAIL)
 
-def create_exclude_file(directory, exclude_file):
-    exclude_file = os.path.join(directory, exclude_file)
+    return True, exclude, rsync_cmd
+
+def create_exclude_file(mydir, exclude_file):
+    exclude_file = os.path.join(mydir, exclude_file)
     with open(exclude_file, "w") as fExclude:
         trace(f"creating exclude-file '{exclude_file}'.")
         fExclude.write("\n")
 
-def create_alias(shell, home_dir, directory, backuppy_script):
+def create_alias(mydir, backuppy_script):
+    shell = os.environ.get("SHELL")
+    home_dir = os.environ.get("HOME")
     # alias entry in .bashrc or .zshrc
-    backuppy_script = os.path.join(directory, backuppy_script)
+    backuppy_script = os.path.join(mydir, backuppy_script)
     alias_str = f"alias backuppy='sudo {backuppy_script}'"
 
     # Check for installed ZSH
@@ -148,37 +121,32 @@ def create_backuppy_script(directory, backuppy_script, rsync_cmd):
     
     os.chmod(backuppy_file, 0o777)  # make file executable
 
-def do_the_install(is_exclude: bool, rsync_cmd: str):
+def do_the_install(mydir: str, exclude_file, is_exclude: bool, backuppy_script: str, rsync_cmd: str):
     """ Creates scripts and entries based on environment variables. """
 
     if is_exclude:
-        create_exclude_file(MYDIR, EXCLUDE_FILE)
+        create_exclude_file(mydir, exclude_file)
 
     if rsync_cmd:
-        create_backuppy_script(MYDIR, BACKUPPY_SCRIPT, rsync_cmd)
-        create_alias(SHELL, HOME, MYDIR, BACKUPPY_SCRIPT)
+        create_backuppy_script(mydir, backuppy_script, rsync_cmd)
+        create_alias(mydir, backuppy_script)
 
 def main(argv):
     trace(f"Starting Backuppy install.py v{VERSION}")
     is_finalized = False
+    mydir = os.getcwd()
 
     if argv and argv[0] == "--gui":
         from install_gui import main_install_gui
         trace("Starting GUI-version.")
-        is_finalized, is_exclude, rsync_cmd = main_install_gui()  # collect user input via GUI and store in env. variables
+        is_finalized, is_exclude, rsync_cmd = main_install_gui(mydir, EXCLUDE_FILE)  # collect user input via GUI and store in env. variables
 
     else:
         trace("Starting CLI-version.\n")
-        is_finalized, is_exclude, rsync_cmd = main_install_cli()  # collect user input via CLI and store in env. variables
-        if is_finalized:
-            print("CLI finalized.")
-        if is_exclude:
-            print("exclude is true.")
-        if rsync_cmd:
-            print("rsync command returned: " + rsync_cmd)
+        is_finalized, is_exclude, rsync_cmd = main_install_cli(mydir, EXCLUDE_FILE)  # collect user input via CLI and store in env. variables
 
     if is_finalized:
-        do_the_install(is_exclude, rsync_cmd)
+        do_the_install(mydir, EXCLUDE_FILE, is_exclude, BACKUPPY_SCRIPT, rsync_cmd)
 
     trace("Ending Backuppy install.py")
 
diff --git a/install_gui.py b/install_gui.py
index 6a3dfae..6d9e1fd 100644
--- a/install_gui.py
+++ b/install_gui.py
@@ -1,7 +1,7 @@
 #!/usr/bin/env python3
 """
 project: Backuppy
-version: 0.8
+version: 0.9
 file: install_gui.py
 summary: python installer-script in GUI-mode (needs PySide2)
 """
@@ -13,12 +13,21 @@ import os
 from PySide2 import QtWidgets
 
 # local imports
-from install import *
+from install import EXCLUDE_FILE, EMAIL
+from utils import set_language, get_lang_text, LANG_EN, LANG_DE
 
 class BackuppyWizard(QtWidgets.QWizard):
-    def __init__(self, parent=None):
+    def __init__(self, parent=None, mydir=os.getcwd(), exclude_file=EXCLUDE_FILE):
         super().__init__(parent)
 
+        # init instance variables
+        self.mydir = mydir
+        self.exclude_file = exclude_file
+        self.exclude = None
+        self.sourcedir = None
+        self.targetdir = None
+        self.rsync_cmd = None
+
         self.setWindowTitle(get_lang_text("intromsg1"))
 
         self.addPage(Page01(self))
@@ -38,11 +47,11 @@ class BackuppyWizard(QtWidgets.QWizard):
 class Page01(QtWidgets.QWizardPage):
     def __init__(self, parent=None):
         super().__init__(parent)
-        self.label = QtWidgets.QLabel("Hello, first of all, which language do you prefer: English or German?")
+        self.label = QtWidgets.QLabel(get_lang_text("welcome"))
 
         self.comboBox = QtWidgets.QComboBox(self)
-        self.comboBox.addItem(LANG_EN, LANG_EN)
-        self.comboBox.addItem(LANG_DE, LANG_DE)
+        self.comboBox.addItem(LANG_EN)
+        self.comboBox.addItem(LANG_DE)
 
         layout = QtWidgets.QVBoxLayout()
         layout.addWidget(self.label)
@@ -50,8 +59,7 @@ class Page01(QtWidgets.QWizardPage):
         self.setLayout(layout)
 
     def validatePage(self):
-        if self.comboBox.currentText() == LANG_DE:
-            set_language(LANG_DE)
+        set_language(self.comboBox.currentText())
 
         return True
 
@@ -77,6 +85,9 @@ class Page02(QtWidgets.QWizardPage):
 class Page03(QtWidgets.QWizardPage):
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self.parent = parent
+
         self.label = QtWidgets.QLabel()
         self.groupbox = QtWidgets.QGroupBox()
         self.groupbox.setFlat(True)
@@ -101,25 +112,26 @@ class Page03(QtWidgets.QWizardPage):
         self.radio1.setChecked(True)
 
     def validatePage(self):
-        global EXCLUDE
         if self.radio1.isChecked():
-            EXCLUDE = True
+            self.parent.exclude = True
         else:
-            EXCLUDE = False
+            self.parent.exclude = False
         return True
 
 
 class Page04(QtWidgets.QWizardPage):
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self.parent = parent
+
         self.label = QtWidgets.QLabel()
         layout = QtWidgets.QVBoxLayout()
         layout.addWidget(self.label)
         self.setLayout(layout)
 
     def initializePage(self):
-        global EXCLUDE
-        if EXCLUDE:
+        if self.parent.exclude:
             self.label.setText(get_lang_text("excludefile2"))
         else:
             self.label.setText(get_lang_text("excludefile3"))
@@ -127,6 +139,9 @@ class Page04(QtWidgets.QWizardPage):
 class Page05(QtWidgets.QWizardPage):
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self.parent = parent
+
         self.label1 = QtWidgets.QLabel()
         self.label2 = QtWidgets.QLabel()
         self.efSourceDir = QtWidgets.QLineEdit()
@@ -154,8 +169,7 @@ class Page05(QtWidgets.QWizardPage):
         self.efSourceDir.setText(dirName)
 
     def validatePage(self):
-        global SOURCEDIR
-        SOURCEDIR = self.efSourceDir.text()
+        self.parent.sourcedir = self.efSourceDir.text()
 
         return True
 
@@ -163,6 +177,9 @@ class Page05(QtWidgets.QWizardPage):
 class Page06(QtWidgets.QWizardPage):
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self.parent = parent
+
         self.label1 = QtWidgets.QLabel()
         self.label2 = QtWidgets.QLabel()
         self.label3 = QtWidgets.QLabel()
@@ -174,7 +191,7 @@ class Page06(QtWidgets.QWizardPage):
 
     def initializePage(self):
         self.label1.setText(get_lang_text("srcdir3_1"))
-        bold_text = f"<p><strong>{SOURCEDIR}</strong></p>" 
+        bold_text = f"<p><strong>{self.parent.sourcedir}</strong></p>" 
         self.label2.setText(bold_text)
         self.label3.setText(get_lang_text("srcdir3_2"))
 
@@ -182,6 +199,9 @@ class Page06(QtWidgets.QWizardPage):
 class Page07(QtWidgets.QWizardPage):
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self.parent = parent
+
         self.label1 = QtWidgets.QLabel()
         self.efTargetDir = QtWidgets.QLineEdit()
         self.pbBrowse = QtWidgets.QPushButton("Browse")
@@ -206,8 +226,7 @@ class Page07(QtWidgets.QWizardPage):
         self.efTargetDir.setText(dirName)
 
     def validatePage(self):
-        global TARGETDIR
-        TARGETDIR = self.efTargetDir.text()
+        self.parent.targetdir = self.efTargetDir.text()
 
         return True
 
@@ -215,6 +234,9 @@ class Page07(QtWidgets.QWizardPage):
 class Page08(QtWidgets.QWizardPage):
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self.parent = parent
+
         self.label1 = QtWidgets.QLabel()
         self.label2 = QtWidgets.QLabel()
         self.label3 = QtWidgets.QLabel()
@@ -226,15 +248,14 @@ class Page08(QtWidgets.QWizardPage):
 
     def initializePage(self):
         self.label1.setText(get_lang_text("targetdir2_1"))
-        bold_text = f"<p><strong>{TARGETDIR}</strong></p>" 
+        bold_text = f"<p><strong>{self.parent.targetdir}</strong></p>" 
         self.label2.setText(bold_text)
         self.label3.setText(get_lang_text("targetdir2_2"))
 
     def validatePage(self):
-        global RSYNC_CMD, MYDIR, SOURCEDIR, TARGETDIR
-        exclude_file = os.path.join(MYDIR, EXCLUDE_FILE)
+        exclude_file = os.path.join(self.parent.mydir, self.parent.exclude_file)
 
-        RSYNC_CMD = f"rsync -aqp --exclude-from={exclude_file} {SOURCEDIR} {TARGETDIR}"
+        self.parent.rsync_cmd = f"rsync -aqp --exclude-from={exclude_file} {self.parent.sourcedir} {self.parent.targetdir}"
 
         return True
 
@@ -242,6 +263,9 @@ class Page08(QtWidgets.QWizardPage):
 class Page09(QtWidgets.QWizardPage):
     def __init__(self, parent=None):
         super().__init__(parent)
+
+        self.parent = parent
+
         self.label1 = QtWidgets.QLabel()
         self.label2 = QtWidgets.QLabel()
         layout = QtWidgets.QVBoxLayout()
@@ -251,9 +275,7 @@ class Page09(QtWidgets.QWizardPage):
 
     def initializePage(self):
         self.label1.setText(get_lang_text("collect"))
-        global RSYNC_CMD
-        #self.label2.setText(f"{RSYNC_CMD}")
-        bold_text = f"<p><strong>{RSYNC_CMD}</strong></p>" 
+        bold_text = f"<p><strong>{self.parent.rsync_cmd}</strong></p>" 
         self.label2.setText(bold_text)
 
 
@@ -274,6 +296,7 @@ class Page10(QtWidgets.QWizardPage):
     def initializePage(self):
         self.label1.setText(get_lang_text("outro1"))
         self.label2.setText(get_lang_text("outro2"))
+        global EMAIL
         urlLink = f"<a href='mailto: {EMAIL}'>{EMAIL}</a>" 
         self.label3.setText(urlLink)
         self.label3.setOpenExternalLinks(True)
@@ -282,14 +305,14 @@ class Page10(QtWidgets.QWizardPage):
         return True
 
 
-def main_install_gui():
+def main_install_gui(mydir, exclude_file):
     app = QtWidgets.QApplication()
-    wizard = BackuppyWizard()
+    wizard = BackuppyWizard(parent=None, mydir=mydir, exclude_file=exclude_file)
     wizard.show()
 
     app.exec_()
 
-    return True, EXCLUDE, RSYNC_CMD
+    return True, wizard.exclude, wizard.rsync_cmd
 
 if __name__ == '__main__':
-    is_finalized, is_exclude, rsync_cmd = main_install_gui()
+    is_finalized, is_exclude, rsync_cmd = main_install_gui(mydir=os.getcwd(), exclude_file=EXCLUDE_FILE)
diff --git a/languages/english.py b/languages/english.py
index e04cfe2..367e77a 100644
--- a/languages/english.py
+++ b/languages/english.py
@@ -9,6 +9,8 @@ Yes="Yes"
 
 No="No"
 
+welcome="Hello, first of all, which language do you prefer: German [DE] or English [EN]?"
+
 languagepack="Perfect, the English language package is now activated. Welcome!"
 
 intromsg1="Thanks for using Backuppy to make your backups!"
@@ -33,7 +35,7 @@ srcdir3_2="if this path is not correct, adjust it in the file 'Backuppy.sh'."
 targetdir1="Now I need to know where Backuppy should save your backups, i.e. the target directory. \n Please enter this carefully and in the same way as for the source directory."
 
 targetdir2_1="you have typed in the following destination path:"
-targetdir2_2="if this path is not correct, adjust it in the file 'backuppy.sh'."
+targetdir2_2="if this path is not correct, adjust it in the file 'Backuppy.sh'."
 
 collect="Now we have almost reached the end of the installer. I will now create the rsync command for you and show it to you.\n If you notice a mistake, just cancel the installer and start again from the beginning.\nNote: I recommend that you download Backuppy completely again in this case."
 
diff --git a/languages/german.py b/languages/german.py
index 07508c9..8836f19 100644
--- a/languages/german.py
+++ b/languages/german.py
@@ -33,7 +33,7 @@ srcdir3_2="wenn dieser Pfad nicht stimmen sollte, dann passe ihn in der Datei 'B
 targetdir1="Nun muss ich noch wissen, wo Backuppy dein Backup ablegen soll, das Zielverzeichnis also.\nBitte tippe dieses gewissenhaft und auf die Weise wie beim Quellverzeichnis ein."
 
 targetdir2_1="du hast folgenden Zielpfad eingetippt:"
-targetdir2_2="wenn dieser Pfad nicht stimmen sollte, dann passe ihn in der Datei 'backuppy.sh' an."
+targetdir2_2="wenn dieser Pfad nicht stimmen sollte, dann passe ihn in der Datei 'Backuppy.sh' an."
 
 collect="Nun sind wir fast am Ende des Installers angelangt. Ich erstelle nun den rsync-Befehl für dich und zeige ihn\ndir nachher nochmal.\nWenn dir da etwas auffallen sollte, brich den Installer einfach ab und fange nochmal von Vorne an.\nAchtung: ich empfehle dir, Backuppy in diesem Fall nochmal komplett neu zu installieren."
 
diff --git a/utils.py b/utils.py
new file mode 100644
index 0000000..ce6df85
--- /dev/null
+++ b/utils.py
@@ -0,0 +1,80 @@
+#!/usr/bin/env python3
+"""
+project: Backuppy
+version: 0.9
+file: utils.py
+summary: utilities script
+"""
+
+# Standard library imports
+import time
+
+# local imports
+from languages import english
+from languages import german
+
+# local globals
+LANG_EN = "EN"
+LANG_DE = "DE"
+LANGUAGE = LANG_EN
+class bcolors:
+    """ Define colors for the std. output to console. """
+
+    OK = '\033[92m' #GREEN
+    WARNING = '\033[93m' #YELLOW
+    ERROR = '\033[91m' #RED
+    RESET = '\033[0m' #RESET COLOR
+
+
+def trace(message_txt, prefix_crlf=False, err=False):
+    """ Print a formatted message to std out.
+
+    :param "message_txt"    [in] The message text that should be displayed.
+    :param "prefix_crlf"    [in] If True, a carriage return/line feed will be done prior to the message text.
+    
+    """
+
+    if prefix_crlf:
+        print("\n")
+    if err:
+        print("[  " + bcolors.ERROR + "ERR" + bcolors.RESET + " ] " + message_txt)
+    else:
+        print("[  " + bcolors.OK + "OK" + bcolors.RESET + "  ] " + message_txt)
+
+def get_lang_text(search_str: str):    
+    """ Returns a string from the appropriate language file. """
+    return_str: str = eval("english."  + search_str) 
+    global LANGUAGE
+    if LANGUAGE == LANG_DE:
+        return_str = eval("german."  + search_str)
+    return return_str
+
+def _print(message_txt: str):
+    print("\n" + get_lang_text(message_txt) + "\n")
+    time.sleep(1)
+
+def set_language(language):
+    """ Set global constant "LANGUAGE" to given language ("EN"/"DE"). """
+    global LANGUAGE, LANG_DE, LANG_EN
+
+    if str(language) and language.upper() == LANG_DE:
+        LANGUAGE = LANG_DE
+    else:
+        LANGUAGE = LANG_EN
+
+def query(question_txt: str):
+    try:
+        answer_txt = input(get_lang_text(question_txt) + "\n> ")
+
+        if not answer_txt:
+            answer_txt = "''"
+
+        if answer_txt.upper() == ":Q" or answer_txt == chr(27):
+            trace("Program exited by user-input.")
+            return None
+
+    except KeyboardInterrupt:
+        trace("Program interrupted by user.", prefix_crlf=True, err=True)
+        return None
+
+    return answer_txt