vinyl phantom

I have a Redsail plotter 24" and sometimes have trouble cutting a simple square? I can have all kinds of other shapes in the file then when it comes to cutting the box it slashes a diagonal cut to the other side or a letter and goes back to cut the same path over and over. I can never tell when it's going to do it unless I pen out the file on paper first. I'm thinking its a low memory problem! Using Redsail RS720c and Flexi starter Desi.

I've been using Endura Gloss for a long time and I believe it's as good or better then Oracal or 3M. I've used them all and I'll stick with the Endura for the cost and quality. It's tough and easy to weed!