Haven't you though about making a game in other full-features engine like unity or godot? The game itself has great potential (and some outdated art in files huh) but from what i can gather it all comes to fighting with plugins and general bad past decisions? This might theoretically take less time to redo and move to other engine than try to fix what's broken beyond repair (like scenes viewer that now has scenes to be ported one by one?).
Otherwise, keep it up, i'll be keeping my eyes on it for sure!