Try cutting parallel spiral cut with the "inside to outside " enabled.It has worked for me.........

I agree with BK on possible solutions,also I would like to add the standard answer that I got............check for an update on your Video card.This was a problem with my system (Windows XP)bombing out......until I got the update.Now I run pretty much error free.(I still get a stray error about every 3 weeks)

How about a "level manager".............that we could step through each level...........to find out what's on each level.........change level's color.....basically do a "layer walk" like mechanical desktop(AutoCad).Just a little suggestion from someone strolling by.

OR............updating your video drivers,,,as silly as that may seem.(2 way's out of a dozen)

Try outputting to iges and then importing as an iges file. This will sometimes clean up "problem files" (just another of a dozen different way's)