Sorry, I missed this one!

What would be good is if the cover art filename allowed absolute paths to be specified, with tokens.

So "cover" means store a file called "cover.[whatever]" in the album folders (this is what happens now).

However, "/covers/<album name>" stores them in the "covers" folder off the root of the library, with the album name as the filename (the same tokens as in the file organisation rule should be used).