Whenever I want to install an Umodded map via UT2004 it shows up as an unknown file type. So I figured I'd allocate Setup as the program with which to open such files. I go browsing, because ít's not in the list by default. When I double click the setup icon in the browse screen, or type in it's path and click open, it doesn't appear in the list.

Does anyone know how to fix this?