UI:

* Fix context.cloth, was not being set correct.
* Fix errors with context pinning, scripts should
  not assume context.object to be there.
* Always show preview even if e.g. the material is not
  set, to keep ID buttons from jumping while you're
  using them.

release/ui/buttons_data_empty.py

@@ -7,7 +7,7 @@ class DataButtonsPanel(bpy.types.Panel):
 	__context__ = "data"
 	
 	def poll(self, context):
-		return (context.object.type == 'EMPTY')
+		return (context.object and context.object.type == 'EMPTY')
 	
 class DATA_PT_empty(DataButtonsPanel):
 	__idname__ = "DATA_PT_empty"
@@ -20,4 +20,4 @@ class DATA_PT_empty(DataButtonsPanel):
 		layout.itemR(ob, "empty_draw_type")
 		layout.itemR(ob, "empty_draw_size")
 		
-bpy.types.register(DATA_PT_empty)
+bpy.types.register(DATA_PT_empty)