Original game menu and no HUD

Hello!
After downloading RTCW and then RealRTCW, I had to relaunch the base RTCW game because the control settings in RealRTCW weren't right (I needed to adjust them in the original game). However, RealRTCW now displays the original game's menu instead of its own, and there is no in-game interface visible at all (neither the original nor the RealRTCW version).
Even uninstalling both of them doesn't change anything.
How can I fix this?
Thanks in advance for your help.