Main map won't work anymore.

[oldrushfan5]

I Know NOTHING about how to change stuff in this game other than with the instructions given in the game itself. (which is not enough for me.) This is the message I get when I start up the game:

The Main HUD Map2_clone_1 window is not compatible with the current client. Please upgrade your UI mod to a compatible verion or revert to the default UI (/loaduidefault).

HUH? I have NO idea how to do this. Does anyone here? Do I have to buy a new version of the game or what?

I'm in the game something of Velios or something like that. Two uprades ago....Anything will help....thanks....ORF