At this point I think it'd be better to just remake JJ3 from scratch in one of modern engines rather than trying to polish the turd. Let's face it - engine used to make JJ3 is OLD and no matter what you'll try, it will never look nearly as good as it could be if made in a modern engine such as Unity.
I could take care about coding as I'm a programmer, but there would be need for level designers, people who'd make textures/models, etc.
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