librocket GUI support

hello fellows

I´m studying libRocket´s tutorial Dragging : http://librocket.com/wiki/documentation/tutorials/Dragging

Everything goes right but when i set icon drag property to clone in tutorial.rss the app run, but when i´m about to drag any icon my app simply crash :confused:

I´m on windows 7 and panda3d 1.8. Any ideas?
Thanx