Oh, I'm sorry. I should have read the post clearer. Firstly, Welcome to MVPMods. Second, the file you are looking for is 58bd.fsh in bkgnds.big, which is located in your data/frontend folder. Because the game is designed with 4:3 screens in mind, the dimensions you are looking for are 1024x1024 which will be resized to a comfortable 1024x768 resolution. Normally what I do is fit the image in 1024x768 and then stretch it out to 1024x1024 than the other way unless you like weird wide pictures. There should be a tutorial floating around somewhere. Give this thread some time and someone else will be able to share some knowledge.