I have the same question as Jack. I want to make a background for my game, but I don't know how. Could you post the code to show how to do this? Thanks!
To fix your problem, I think you would need to load a GRP with the background you want. To do this, at the beginning just put LOAD "GRP5:YOURBG", FALSE. This loads the GRP in GRP slot 5 (BG), and then skips the dialogue for loading the file. Then after that, just put GPAGE 5,5 to set the graphic page as your GRP. Hope this helps!