I'm no 3D expert but its my impression that t-juntions such as the one in the image at the top is an industry no-no. It'll cause lighting errors and looks sloppy overall.
I've had that too... was wondering if it was some sort of mesh error on my part.. one vert would be stuck to the bottom left corner and be completely unselectable.
I would try contacting the developer and ask for help. Have you looked at the script editor / output window when running the plugin, are there any error messages?
Thanks for the reply poopipe ,but when painter crash there is no option to report it .... (painter quit without any error message to the desktop... after quit a long computing process )