I'm the primary author. I don't load everything in a uniform interface, that would be a disaster for accuracy, so each game loads roughly from its raw data form

I'm the primary author. I don't load everything in a uniform interface, that would be a disaster for accuracy, so each game loads roughly from its raw data formats. That's why different games are at different levels of "completion", some have enemies and animations and lighting, some are very poor with just a "base" level model displayed.