Not a biggy, but existed on #6000 too. After a fresh portable install, the initial Wacup window for Lyrics overlaps the one for Album Art, so when you close or move Lyrics, the AlbumArt magically appears under it. This may cause some frustration for users trying to activate the AlbumArt window in vain. Perhaps the non-portable edition also exhibits the same behaviour.
By the way, it would be very nice if the Album Art window first appeared as a square one, to avoid having to resize it manually, since it's rather difficult to set it to an exact 1:1 aspect ratio (a visual indication for that would be nice). Hopefully in build #142857

EDIT: Where are my manners? Happy musical new year to all developers, testers and users!