diff --git a/AttributeEditor.py b/AttributeEditor.py
index 7ec7da83..ba13b175 100644
--- a/AttributeEditor.py
+++ b/AttributeEditor.py
@@ -229,7 +229,7 @@ def __init__(self, parent, id, model):
 		else:
 			xm,ym = self.ScreenToClient(wx.Point(xwindow, ywindow))
 
-		self.SetPosition((xm,ym))
+		self.SetPosition((int(xm),int(ym)))
 
 		#default value for spinCtrl
 		self._sb_input.SetValue(model.input)
diff --git a/devsimpy.py b/devsimpy.py
index aa26d48e..994f8e1f 100644
--- a/devsimpy.py
+++ b/devsimpy.py
@@ -101,6 +101,7 @@
 import wx.py as py
 import wx.lib.dialogs
 import wx.html
+import wx.lib.mixins.inspection as wit
 
 try:
 	from wx.lib.agw import advancedsplash
@@ -1712,7 +1713,7 @@ def StartSimulationGUIWin(self, arg, diagrams):
 							g = 15*i
 							x = dw - w + g
 							y = dh - h + g
-							simFrame.SetPosition((x/2, y/2))
+							simFrame.SetPosition((int(x/2), int(y/2)))
 	
 							simFrame.SetWindowStyle(wx.DEFAULT_FRAME_STYLE | wx.STAY_ON_TOP)
 
@@ -2366,7 +2367,7 @@ def flush(self):
 		pass
 
 #-------------------------------------------------------------------
-class DEVSimPyApp(wx.App):
+class DEVSimPyApp(wx.App, wit.InspectionMixin):
 
 	outputWindowClass = PyOnDemandOutputWindow
 
@@ -2451,6 +2452,9 @@ def OnInit(self):
 		the main frame when it is time to do so.
 		"""
 
+		# initialize the inspection tool (enabled with Ctrl+Alt+I)
+		self.Init()
+
 		# Check runtime version
 		if wx.VERSION_STRING < __min_wx_version__:
 			wx.MessageBox(caption=_("Warning"),
diff --git a/plugins/state_trajectory.py b/plugins/state_trajectory.py
index a6f9e1fa..de91b246 100644
--- a/plugins/state_trajectory.py
+++ b/plugins/state_trajectory.py
@@ -23,24 +23,9 @@
 import subprocess
 import importlib
 
-required_libs = ['matplotlib']
-
-for lib_name in required_libs:
-    try:
-        importlib.import_module(lib_name)
-    except:
-        subprocess.run(f'pip install {lib_name}'.split())
-
-#import matplotlib.pyplot as plt
-
 import wx.lib.agw.aui as aui
 #import wx.lib.mixins.inspection as wit
 
-import matplotlib as mpl
-from matplotlib.backends.backend_wxagg import (
-    FigureCanvasWxAgg as FigureCanvas,
-    NavigationToolbar2WxAgg as NavigationToolbar)
-
 class PlotPanel(wx.Panel):
     def __init__(self, parent, id=-1, dpi=None, **kwargs):
         wx.Panel.__init__(self, parent, id=id, **kwargs)
@@ -206,7 +191,7 @@ def PlotStateTrajectory(m):
             dial = wx.MessageDialog(None,
                             _('Select at least one decorate transition function for %s.')%label,
                             _('Plot Manager'),
-                            wx.OK | wx.ICON_EXCLAMATION)
+                            wx.OK | wx.ICON_EXCLAION)
             dial.ShowModal()
     else:
         dial = wx.MessageDialog(None,