I just want to let it be known that this question inspired me to work on the conversion project again. There's still a lot to do before it's minimally usable (event system, drawing manager, networking and a lot of ui), but progress is progress. Since I'm practically rewriting it from scratch, I'm trying to make it a more generic vector drawing program with dod support from the start rather than a dod client with some vector support like the old one is. And I get to structure the code better (hopefully >.<). But the more differences there are, the less I can just convert from the old code...