MOH Rad is a buggy piece of s**t - and its not the best editor out there:
UnrealEd 2 - for the new Unreal Tournament 2003 is a far superior editor - it features dynamic lighting and compiling takes seconds rather than hours.
GTK Radiant - A user made version of Radiant - hopefully soon to support MoHAA is Scorpio can figure out a way to help them - Its far more stable and has many many more options / plugins