From my research XP machines can't run current GameMaker Studio games w/o getting that "not a valid Win32 application" message. This was made in GMS 1.4 (I said "8" below, must've been tired or something haha!). I also just looked and it seems GMS 2.1, which I use now, also has this issue. I'm not sure there is a solution. I'm sorry.
Have you played any games you know to be made in GameMaker Studio on your machine? I'm thinking it was when they jumped from just "Game Maker" to "Studio" that XP stopped being supported.
I really appreciate that you liked the look of the game enough to check back. It means a lot!