ReptileAssassin

Yep, that was the problem. They now work like a dream. Thank you for replying anyway.

Well I feel like a complete idiot. I had created the Set step of the pieces (the second one, which does the destroying) after I had programmed the 1rst and 3rd parts.

As a result, most of the pieces have not been programmed yet to enter step 2 instead of 3.

Doy.

I'll finish programming it and bump this thread if they still do not work.

That might be the problem. In any event it's a LOT more efficient to just tile it anyway since you're dealing with a repeating pattern. Like I said make it just four squares and tile it and you'll get the same background with a much smaller sprite. This will make the game load faster too!

No, the boards themselves are one sprite each, but they are not the gigantic background. The background I'm talking about is a spacey background that I'm pretty sure cannot be tiled.

How big is your background? Is it a .bmp? GM doesn't handle huge resources very well. (at least older versions didn't) Try changing your background to just 4 squares and then tile it (check off tile hor and tile vert in the room background options).

I'm using GM 8.1 Standard.

And I was hoping the background size wasn't the problem....

It's 3600 by 2430  JPEG

Sorry about before. I was tired and distracted by 6 things at once, so I honestly didn't even read LOS.A's post. He was indeed right (well, viewport, not room, but similar). If your room is squished on your screen, the coordinates relative to the room won't equal the coordinates on the screen. But as asked before, why is your viewport larger than your screen?

Yes, scaling it down to 90% will work, but a better way is to keep it at 100% and just make the viewport smaller. As in, small enough to fit in an average monitor.

-IMP

I actually did not mess with anything. I don't even know what a viewport is or how to mess with it, unless you're talking about the view settings. I still did not mess with those though. I just built the room with the objects in it and let it go at that.

But anyway, the problem is solved. Now the headache I'm dealing with is the background randomly becoming a bad graphic and preventing game launch. It works for a while, but then it suddenly decides to give me an Unexpected Error message until I delete and re-add the exact same thing