Mac/Pc UI Problems?

[Bexl]

So I love making my own custom UI's and I have been making some for friends recently.

I've encountered a problem in the compression/transferring of specifically the WTF folders and various artwork. I work on a mac, my friends have PC's. Is there anything special I'm supposed to be doing in the compression stages that I'm missing? Will WTF folders transfer over platforms?

I can post a screenie if needed.