Hi there
I wanted to palce some custom models in my map by radiant the fact is that some of them do work,
but some like the world model of some custom weapons and another one make radiant crash
with this error:
FATAL ERROR: Unhandled exception caught
GetLastError()=0
An unrecoverable error has occured.Would you like to edit preferences before exiting q3Radiant.

It must be a model problem since it crashes on any map i try on.
And even a friend of mine tried the models and still made radiant crash on him!
These model that i am trying to place(ie. worldmodel of a weapon) do work as worldmodel ingame, they just make radiant crash, not the game!

How many mb is the xmodel export?
How many verts/faces does the model have in tomxmodel utils?
Did you try to export and reimport?