I managed to fix the key glitch, that seems to have to do with RAM and GameMaker. GameMaker does not read the keys directly from the keyboard but instead stores the information of which key has been pressed or released in the memory, this seems to mean that on some PCs the game will forget which key is being pressed or released if a lot of keys are being pressed. I didn't notice it on my PC cause I've got quite a bit of RAM but the moment I tried it out on my school computer I saw the glitch in action. I've reworked the game to read straight from the keyboard. This unfortunatly also means that the game will still respond to keys if minimized. I'll try find a way around this. So far only the arrow keys are affected by this change.
The background problem seems to be a compilation error on my part but is fixed now. ^_^ Hopefully all glitches are fixed.
Edit: Also the new version is compiled through GameMaker7 so it should work on Vista without need of conversion.
Edit2: Also I was wondering if I should change the Malco robots at the beggining to Balrog minions, or would that be too much like Tale of the Broxxus?
Edit3: Sigh... A lot of edits... Last one: what do you think of my Surface Soldier FacePic?