I’m using GTK Radiant 1.4 to create a map for Jedi Outcast; When I texture a curved surface the texture seems compressed and I can’t use the Crl + Shift + Left Click to select just a single face of the surface. (this happens on end capped curves only)

And another problem I encountered was that when I right click on the grid area, there is no NPC item selection!

I'm going to assume you're doing a patch mesh. Select the entire mesh just using Shift + LClick, then open up the Patch Inspector thingy by hitting Shift + S. Play around in the settings there.

Many of the entities are left out of the list in Radiant. You'll have to manually change the classname => value to NPC_npcname. There's probably a list somewhere...Echoman?

Yeah, I beat him.

blast

About the NPC trouble, are you sure you are not in Multiplayer editing mode?