Ah yes, I'm aware of that. Though I wouldn't so much say "There is a Glover 2" as "There could have been a Glover 2", which of course is a tremendous shame because the unfinished game looked interesting, if a little trying too hard to be Banjo-Kazooie.
Glover has hardly anything in common with Portal IMO. And Glover 2 isn't complete, so I'd hardly call it "playable" even if one did track down the ROM of it.