Ehh... this is what happens when you get an inexperienced programmer making a program reader: a spaghetti mess that creates extremely unintuitive bugs. Thank you so much for your effort in tracking this down as far as you could. I will be working on ironing out the bugs now (working from a new GameMaker version introduced its own fair share of them... one of them is that I can't type the letter "i", although if I use the debugger to stop at a certain line of code, I can. Ugh.)
If you have any other complaints about game design and such, let me know please. It's nice to have such a dedicated community.