Another option is to have two categories, open and closed source. I guess it really depends on what the competition is about. Is it purely promoting the fact that pascal is a capable language for coding games, or is it for promoting the use of pascal to code games?

If it's the latter, then an open source idea would be far more useful. Perhaps the entries could be dual judged - "Complete Game" and "Complete Game as a Tutorial"? This could extend to design docs, etc. Teams could choose not to enter a category if they wish.

Just a suggestion...