diff --git a/NodeGraphQt/base/graph.py b/NodeGraphQt/base/graph.py
index 9d5c8346..0c8eef89 100644
--- a/NodeGraphQt/base/graph.py
+++ b/NodeGraphQt/base/graph.py
@@ -1368,9 +1368,12 @@ def _deserialize(self, data, relative_pos=False, pos=None, set_parent=True):
                 for prop in node.model.properties.keys():
                     if prop in n_data.keys():
                         node.model.set_property(prop, n_data[prop])
+                        
                 # set custom properties.
                 for prop, val in n_data.get('custom', {}).items():
                     node.model.set_property(prop, val)
+                    if prop in node.view.widgets:
+                        node.view.widgets[prop].set_value(val)
 
                 nodes[n_id] = node
 
diff --git a/NodeGraphQt/qgraphics/node_base.py b/NodeGraphQt/qgraphics/node_base.py
index 13838f02..ebaef9a2 100644
--- a/NodeGraphQt/qgraphics/node_base.py
+++ b/NodeGraphQt/qgraphics/node_base.py
@@ -676,7 +676,7 @@ def _delete_port(self, port, text):
             port (PortItem): port object.
             text (QtWidgets.QGraphicsTextItem): port text object.
         """
-        port.delete()
+        [pipe.delete() for pipe in port.connected_pipes]
         port.setParentItem(None)
         text.setParentItem(None)
         self.scene().removeItem(port)
diff --git a/NodeGraphQt/widgets/viewer.py b/NodeGraphQt/widgets/viewer.py
index c6ba176d..65bd220e 100644
--- a/NodeGraphQt/widgets/viewer.py
+++ b/NodeGraphQt/widgets/viewer.py
@@ -169,10 +169,7 @@ def _set_viewer_pan(self, pos_x, pos_y):
             pos_x (float): x pos.
             pos_y (float): y pos.
         """
-        speed = self._scene_range.width() * 0.0015
-        x = -pos_x * speed
-        y = -pos_y * speed
-        self._scene_range.adjust(x, y, x, y)
+        self._scene_range.adjust(pos_x, pos_y, pos_x, pos_y)
         self._update_scene()
 
     def scale(self, sx, sy, pos=None):
@@ -413,9 +410,10 @@ def mouseMoveEvent(self, event):
             zoom = 0.1 if pos_x > 0 else -0.1
             self._set_viewer_zoom(zoom, 0.05, pos=event.pos())
         elif self.MMB_state or (self.LMB_state and self.ALT_state):
-            pos_x = (event.x() - self._previous_pos.x())
-            pos_y = (event.y() - self._previous_pos.y())
-            self._set_viewer_pan(pos_x, pos_y)
+            previous_pos = self.mapToScene(self._previous_pos)
+            current_pos = self.mapToScene(event.pos())
+            delta = previous_pos - current_pos
+            self._set_viewer_pan(delta.x(), delta.y())
 
         if self.LMB_state and self._rubber_band.isActive:
             rect = QtCore.QRect(self._origin_pos, event.pos()).normalized()
diff --git a/example_auto_nodes.py b/example_auto_nodes.py
index 103abd6e..8b881d22 100644
--- a/example_auto_nodes.py
+++ b/example_auto_nodes.py
@@ -1,7 +1,8 @@
 #!/usr/bin/python
 # -*- coding: utf-8 -*-
 from NodeGraphQt import NodeGraph, setup_context_menu, \
-    QtWidgets, QtCore, PropertiesBinWidget, BackdropNode
+    PropertiesBinWidget, BackdropNode
+from Qt import QtWidgets, QtCore
 from example_auto_nodes import Publish, RootNode, update_nodes, setup_node_menu
 import importlib
 import inspect
diff --git a/example_auto_nodes/input_nodes.py b/example_auto_nodes/input_nodes.py
index fb158574..4daa16ea 100644
--- a/example_auto_nodes/input_nodes.py
+++ b/example_auto_nodes/input_nodes.py
@@ -1,4 +1,4 @@
-from NodeGraphQt import QtCore
+from Qt import QtCore
 from NodeGraphQt.constants import (NODE_PROP_VECTOR2,
                                    NODE_PROP_VECTOR3,
                                    NODE_PROP_VECTOR4)