Jedi knite is made around .BSP files isnt it? Could you use the half-life worldcraft editor? If you can i will start up a mod going cos i can map with worldcraft. Im not a big fan if the Q3 level editor..
BSP versions vary, well their version numbers and contents do anyway.
As for using Worldcraft I have no idea, tbh I would be surprised as hell if that were the case. You could always test it out and compile, see how it comes out!
id go nowhere without an fgd or the names if the player start... Is it info_player_start?
And does it use Qbsp and Qrad or vis (programs) ect... to compile it?
As much as I miss good ol' WorldCrash, Gtk is better.
I set up my GTK, to have the quartered view, with camera, and the 3 2d views all at once... I don't see how people can stand toggling back and forth between views, seems like a waste of time to me...
Anyway, you should just start getting used to GTK... I had some trouble with it at first, but it's extremely customizable.
I don't think WorldCrash (or Hammer, whatever it's called now) would be able to support q3 based maps anyway.
Although I have never even seen worldcraft, I would just like to point out that there's no magic in the maps. The map editor doesn't understand .bsp, only .map files, and they are standard text files you can open with Notepad. So, you can compare a worldcraft file with a Radiant .map file. If they look the same (and providing you can also access the entities and such) there's no reason why you couldn't use what editor you prefer. (This also means one could map with a Notepad! I wonder what kind of map you could do with just a Notepad. There should be a competition someday. What a challenge!).
If they look different, you could perhaps code a program to do the conversion. After all, if worldcraft also saves it's product as a text file, you could edit it quite easily, although the actual layout, or let's be correct and say file format, might be something that would take some time to learn.
To sum it all up: I wouldn't go through the trouble...