IPete - I think you should say that it's strictly forbidden to sell a product that was made with the unreal engine. He may modify Levels (hence Modders) or create his own levels, he will not be allowed to sell them unless he purchases a publisher license. AFAIK he also isn't allowed to release a game (that includes the engine) for free.
It is a good way to learn something, if he's very talented, he may even find a job in the business (no illusions please), but it isn't an engine you can use to release your game to the public.
It is a good way to learn something, if he's very talented, he may even find a job in the business (no illusions please), but it isn't an engine you can use to release your game to the public.