I updated the extension and everything seems normal in the console, but I can't actually use the extention.

/copy doesn't work at all (no error shown) and /paste keeps telling me "file does not exist".

Hey there. Please show the exact setup you have (folder/file structure screenshot from FTP or such for your data files). Try changing copypaste folder name to lowercase "copypaste" or the other way "CopyPaste". We'll also need the exact command/s you're trying to run.

The commands are literally just /copy <filename> and /paste <filename> with no other options included.

File structures: 

Indeed but please still send the EXACT command you're running, including the file name. That helps investigate regardless of how useless you think it is. Try renaming the `data/CopyPaste` folder to `data/copypaste`.