After a few hours I figure it out how to fix the bug splat, I have a heavy model, every time that I started using the slice tool my model crashed up, I tryed exploding the model, chainging to newer sketch up, etc etc etc. At the end I took all the model and grouped up whith out the cuting plane, after I slice it, and was the solution for the problem, now it doesn't matter how heavy is the file, the plug in ,work fine. sorry for my bad english, I hope is useful for you.

thanks the program is really good, shame that I have the same problem, I can not make a slice cut (bug splat) when the model is a litle bit heavy, anyways thanks and keep on.