diff --git a/printrun/gviz.py b/printrun/gviz.py
index 11ffe65..05f0bdd 100755
--- a/printrun/gviz.py
+++ b/printrun/gviz.py
@@ -185,7 +185,6 @@ class gviz(wx.Panel):
     def layerdown(self):
         if self.layerindex > 0:
             self.layerindex -= 1
-            # Display layer info on statusbar (Jezmy)
             self.parent.SetStatusText("Layer %d - Going Down - Z = %.03f mm" % (self.layerindex + 1, self.layers[self.layerindex]), 0)
             self.dirty = 1
             wx.CallAfter(self.Refresh)
@@ -353,7 +352,6 @@ class gviz(wx.Panel):
                 arc = [_x(start_pos[0]), _y(start_pos[1]),
                        _x(target[0]), _y(target[1]),
                        _x(start_pos[0] + target[5]), _y(start_pos[1] + target[6])]
-                # FIXME : verify this works : why not reverse endpoints 4, 5
                 if gline.command == "G2":  # clockwise, reverse endpoints
                     arc[0], arc[1], arc[2], arc[3] = arc[2], arc[3], arc[0], arc[1]
 
@@ -378,12 +376,12 @@ class gviz(wx.Panel):
         def _x(x):
             return x - self.build_dimensions[3]
 
-        start_pos = self.hilightpos[:] if hilight else self.lastpos[:]
-
         if gline.command not in ["G0", "G1", "G2", "G3"]:
             return
+
+        start_pos = self.hilightpos[:] if hilight else self.lastpos[:]
         
-        target = self.hilightpos[:] if hilight else self.lastpos[:]
+        target = start_pos[:]
         target[5] = 0.0
         target[6] = 0.0
         if gline.x != None: target[0] = gline.x
@@ -417,6 +415,7 @@ class gviz(wx.Panel):
             if gline.command == "G2":  # clockwise, reverse endpoints
                 arc[0], arc[1], arc[2], arc[3] = arc[2], arc[3], arc[0], arc[1]
 
+            if not hilight:
                 self.arcs[z].append(arc)
                 self.arcpens[z].append(self.arcpen)
             else:
diff --git a/pronterface.py b/pronterface.py
index 3fb7e0d..f23954d 100755
--- a/pronterface.py
+++ b/pronterface.py
@@ -121,7 +121,7 @@ class PronterWindow(MainWindow, pronsole.pronsole):
         self.skeinp = None
         self.monitor_interval = 3
         self.paused = False
-        self.sentlines = Queue.Queue(30)
+        self.sentlines = Queue.Queue(0)
         self.cpbuttons = [
             SpecialButton(_("Motors off"), ("M84"), (250, 250, 250), None, 0, _("Switch all motors off")),
             SpecialButton(_("Check temp"), ("M105"), (225, 200, 200), (2, 5), (1, 1), _("Check current hotend temperature")),
@@ -256,7 +256,7 @@ class PronterWindow(MainWindow, pronsole.pronsole):
                     pass
             try:
                 self.sentlines.put_nowait(line)
-            except:
+            except Queue.Full:
                 pass
             #threading.Thread(target = self.gviz.addgcode, args = (line, 1)).start()
             #self.gwindow.p.addgcode(line, hilight = 1)
@@ -1091,11 +1091,8 @@ class PronterWindow(MainWindow, pronsole.pronsole):
                     break
                 time.sleep(0.25)
             while not self.sentlines.empty():
-                try:
-                    gc = self.sentlines.get_nowait()
-                    wx.CallAfter(self.gviz.addgcode, gc, 1)
-                except:
-                    break
+                gc = self.sentlines.get_nowait()
+                wx.CallAfter(self.gviz.addgcode, gc, 1)
         wx.CallAfter(self.status.SetStatusText, _("Not connected to printer."))
 
     def capture(self, func, *args, **kwargs):