I have a song in my library that won't delete it says it is being used by another application or being downloaded to how do i delete it it shows up red and not black like the others in the library

If a file has red text, just means that it's not being shared.

If the file is incomplete, go to your LW library, click on 'Incomplete Files' & then click Explore...your incomplete folder will open outside of LW. Keep that folder open, close LW & once LW's closed, delete the file from your incomplete folder.

If the file isn't incomplete, go to LW's library & click on Saved Files, highlight the file & click Explore....same deal when the folder opens; completely close LW & try to delete from the saved folder.

If that doesn't work, try deleting in safe mode or use one of the utilities in this thread below.
Incomplete Download File won't delete at all.