Strange Random GameMaker Behavior

My code was working beautifully. I save it, and I went to bed.

I open the same project this morning, and the program is behaving strangely when I run my app.

I hunt around, looking at my code, checking instances in layers. I make "NO" changes to anything, and when I run the program, the behaviors change.

I have no idea what to make of this.

One very interesting, but frustrating problem in particular happens during instance collection:

I run code that simply collects all the instance...

Strange Random GameMaker Behavior