Thankfully, I've managed to recruit outside help in beginning the transition of the mod from HL2E2 map files to a full-fledged individual codebase. This will take time, but this is a big step forward for the mod overall. It's still very early, things are being debugged, but hopefully the next public release of the mod will be riding atop this codebase. I've got some good ideas for how to best push the mod's ideas with code modification, but these will require extensive testing to ensure it doesn't break existing map balance (as Prison's been tested extensively by myself and many others, I want to use that as a testing ground to ensure any changes are beneficial for the overall experience).
Thanks for all of you that continue to follow the mod, and I hope to bring more good news to you soon in the coming months.