Did you look at the link I gave? Perhaps the file is actually finished or almost finished anyway. So if it plays to the end or until end titles then perhaps you can remove it from download folder, then cancel it from download window.

I did. Unfortunately it's not finished (about 49mb left), I think imma continue downloading the corrupted file and see how it goes.

Also Frostwire is a great app, I just hope that it has a manual hash check option (like Limewire? I can't remember) and remember which files did I pause when I reopen the app.