I bought this app yesterday, had no problems with it and everything worked fine. After restarting my PC and coming back to it however, none of my characters are loading, every menu dropdown shows layer 0, layer 1 etc, and the image folder is apparently empty. 

Other than restarting my PC, I have changed literally nothing.

SOLVED:
Managed to work out the issue! The program didn't like me having the Clip Studio source file saved in the images folder.