To remove tape residue from any sort of hard surface, I've always used more tape and stick it onto the sticky residue. Pull it off quickly and repeat the process. Eventually it'll pull everything off with no harm done, or any sticky residue left from rubbing the surface.
I also haven't PM'd you (Ivan) a final count on missing / damaged keys. :x Will GMK be allowing more "missing key" orders, or are they sending enough to cover everything?