i had the same problem. I was doing two grooves in the same tool path. I changed and did a separate tool path for each groove and that worked.

I am using Mastercam X9 I have successfully created a lathe custom tool in a level within the same file I am working on. When I back plot this tool everything is fine, but in verification mode, the holder is a lot bigger and the cutter a lot smaller than what I designed and shows a crash in verification. Any ideas why this is happening? Thank you in advance for any tips or ideas.