itch.io

i was trying to figure out how to add my own files from MAC system and in the midst of it, the original sprite is also gone.... it says "failed to add sprite, file not found"...ive tried to redownload the application etc but nothing works as well.... im really new to this so alot of basic knowledge is almost non-existent and the OS system really doesnt help ;A; im so srry 

may i ask how did u import files on mac