All my imports broke? o.o

[TeMaRi]

Eh I'm kinda new to World Editor, if only a little, and I had gotten quite a few imported models on a map me and my friend had started working on. Well I was using the StarCraft models that I got from this site when suddenly all of my imports broke and changed to 0KB file size. I've tried restarting the editor and my computer, but to no avail. Has anyone ever heard of this, or could you try to help me fix it, or at least figure out what went wrong? My friend has a working copy of the map so I should be able to get it from him, but if this is going to keep happening, that could hinder the progress.

Thank you for any and all support in advance.

Also if it helps at all, they had been working fine for about 7 hours, I had tested them all and only a couple weren't working, and then everything sort of went to hell and I'm now unable to progress.