diff --git a/.travis.yml b/.travis.yml
index 15606ee2..460aee40 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -39,7 +39,7 @@ addons:
 install:
   - travis_wait 50 pip install -U -f https://extras.wxpython.org/wxPython4/extras/linux/gtk3/ubuntu-14.04 wxPython
   - travis_wait 50 python setup.py install
-  - pip install PyPubSub==3.3.0 pyyaml ruamel.yaml requests
+  - pip install PyPubSub==3.3.0 pyyaml ruamel.yaml
 
 # command to run
 script: travis_wait 20 python devsimpy.py examples/model0.dsp quit
\ No newline at end of file
diff --git a/Decorators.py b/Decorators.py
index 6f637be6..3018ea7d 100644
--- a/Decorators.py
+++ b/Decorators.py
@@ -146,18 +146,44 @@ class ThreadWithReturnValue(threading.Thread):
 	def __init__(self, *args, **kwargs): 
 		super(ThreadWithReturnValue, self).__init__(*args, **kwargs) 
 		self._return = None
+		self.killed = False
+  
+	def start(self): 
+		self.__run_backup = self.run 
+		self.run = self.__run       
+		threading.Thread.start(self) 
 	
-	def run(self):
-		if self._target is not None:
-			try:
-				self._return = self._target(*self._args, **self._kwargs)
-			except Exception as e:
-				self._return = e
+	def __run(self): 
+		sys.settrace(self.globaltrace) 
+		self._return = self.__run_backup() 
+		self.run = self.__run_backup 
+	
+	def globaltrace(self, frame, event, arg): 
+		if event == 'call': 
+			return self.localtrace 
+		else: 
+			return None
+	
+	def localtrace(self, frame, event, arg): 
+		if self.killed: 
+			if event == 'line': 
+				raise SystemExit()
+		return self.localtrace 
+	
+	def kill(self): 
+		self.killed = True
+
+	# def run(self):
+	# 	if self._target is not None:
+	# 		try:
+	# 			self._return = self._target(*self._args, **self._kwargs)
+	# 		except Exception as e:
+	# 			self._return = e
 			
-	def join(self):
-		if not isinstance(self._return, Exception):
-			threading.Thread.join(self)
-		return self._return
+	# def join(self):
+	# 	if not isinstance(self._return, Exception):
+	# 		threading.Thread.join(self)
+	# 	return self._return
 
 @decorator_with_args
 def ProgressNotification(f, arg):
@@ -175,13 +201,17 @@ def wrapper(*args):
 		thread = ThreadWithReturnValue(target = f, args = args)
 		thread.start()
 
-		while thread.isAlive():
-			wx.MilliSleep(300)
-			progress_dlg.Pulse()	
-			wx.SafeYield()
+		while thread.isAlive():			
+			if progress_dlg.WasCancelled() or progress_dlg.WasSkipped():
+				thread.kill()
+				break
+			else:
+				wx.MilliSleep(300)
+				progress_dlg.Pulse()
+				wx.SafeYield()
 
 		progress_dlg.Destroy()
-		
+
 		return thread.join()
 
 	return wrapper
diff --git a/Utilities.py b/Utilities.py
index ec53d64c..1db5b49e 100644
--- a/Utilities.py
+++ b/Utilities.py
@@ -65,8 +65,6 @@
 import fnmatch
 import urllib.request, urllib.parse, urllib.error, urllib.request, urllib.error, urllib.parse, http.client
 from urllib.request import urlretrieve
-
-import requests
 	
 import pip
 import importlib
@@ -182,8 +180,9 @@ def check_internet():
 	url = 'https://github.com/capocchi/DEVSimPy'
 	timeout = 5
 	try:
-		_ = requests.get(url, timeout=timeout)
-	except requests.ConnectionError as e:
+		
+		_ = urllib.request.urlopen(url, timeout=timeout)
+	except Exception as e:
 		print(e)
 		return False
 	else:
@@ -209,22 +208,18 @@ def downloadFromURL(url):
 	"""
 	
 	try:
-		# downloading with requests
+		# downloading with request
 		# download the file contents in binary format
-		r = requests.get(url)
-	except requests.ConnectionError as e:
+		r = urllib.request.urlopen(url)
+	except Exception as e:
 		print(e)
 		return None
 	else:
-		if r.status_code == 200:
+		if r.getcode() == 200:
 		# 200 means a successful request
 			
 			tempdir = tempfile.gettempdir()
 			fn = os.path.join(tempdir, "DEVSimPy.zip")
-			# open method to open a file on your system and write the contents
-			with open(fn, "wb") as code:
-				code.write(r.content)
-			
 			# downloading with urllib	
 			# Copy a network object to a local file
 			urlretrieve(url, fn)
@@ -244,23 +239,23 @@ def updateFromGit():
 	if fn:
 		# opening the zip file in READ mode 
 		with ZipFile(fn, 'r') as zip:
-			txt = 'Name / Size / Date\n'
-			txt +=' \n'.join([str(elem.filename)+'/'+str(elem.file_size)+'/'+str(elem.date_time) for elem in zip.infolist()]) 
 			# printing all the contents of the zip file 
-			dlg = wx.RichMessageDialog(None, "Do you realy want to update DEVSimPy?\nAll files will be relaced and you cannot go backwards.", style=wx.YES_NO|wx.CENTER)
-			dlg.ShowDetailedText(txt)
-			if dlg.ShowModal() not in (wx.ID_NO, wx.ID_CANCEL):
+			#dlg = wx.RichMessageDialog(None, "Do you realy want to update DEVSimPy?\nAll files will be relaced and you cannot go backwards.", style=wx.YES_NO|wx.CENTER)
+			#txt = 'Name / Size / Date\n'
+			#txt +=' \n'.join([str(elem.filename)+'/'+str(elem.file_size)+'/'+str(elem.date_time) for elem in zip.infolist()]) 
+			#dlg.ShowDetailedText(txt)
+			#if dlg.ShowModal() not in (wx.ID_NO, wx.ID_CANCEL):
 		
-				# extracting all the files 
-				print('Extracting all the files now...') 
-				#zip.extractall()
-				print('Done!')
+			# extracting all the files 
+			print('Extracting all the files now...') 
+			#zip.extractall()
+			print('Done!')
 
-				dlg.Destroy()
-				return True
-			else:
-				dlg.Destroy()
-				return False  
+			#dlg.Destroy()
+			return True
+			#else:
+			#	dlg.Destroy()
+			#	return False  
 	else:
 		return False