Okay, what are the errors you're getting (if they're not in Japanese that is)? Just "cannot create project?"
If that's the case, I suggest changing your project directory to a folder that actually exists - by default it sticks it in something like C:\Program Files\Enterbrain\RPG2003 , though this may have changed since I installed it a long, long time ago. If you installed it to something like D:\Games\RM2k3 then it's still looking in its default directory, which doesn't exist.
Another issue could be low disk space, though that's probably not the cause.
Even more unlikely would be that you don't have Write/Create rights to the folder you're putting it in. That's probably not going to be the case unless you're trying to stick it someone else's My Documents folder or something.
Threaded Mode