Damn… stupid bugs. What should have taken just an afternoon, took like 3 days to sort out. All because I got sloppy with naming rules between macros (names for the script functions), the related function in the list, and the var associated with the function. All too close in label name (actually just a difference of capital letters at the tail end). Dammit. Anyway, object to collision map and detection logic is working great now (for the main ship). Need to apply it to the ships bullets and just objects in general that get put into the collision list. Then I can move on to object-to-object collision routine.