toxinMafs

Is there a way to preserve a palette at 100% fidelity? I'm working with an old old game (Wolfenstein 3D) and an editing program which requires a very specific 256-color palette; how can I achieve this? Bitmaps. MS Paint does it automatically when you save the file to "256-color bitmap", but I can seem to get paint.net to do this. Thank you very much for help, and I'll be sure to pass along the information.