You mean 'default.dms', right? That's for the Dream Seeker's settings. He wants to reset the settings for Dream Maker. :\
Oh, whoops. I was actually referring to the color palette on DreamMaker's icon editor, but I just realized we don't even save that anymore. To reset the settings for DreamMaker's code, delete the file called 'maker.txt'.
Search for & delete the file called 'default.dmi' in your BYOND config directory. That will restore your settings.