1. Ijed and RickyT23 released two RMQ speedmaps. You can run those either with the SP Demo 2 (create a new folder “maps” next to the pak file, and copy the .bsp files there) or with a newer progs etc. (170 MB download).
2. SP Demo 3 is on a hiatus induced by technical obstacles and RL requirements. There is no release date atm.
3. There is continuing work on new enemies, weapons, a really nice new monster roaming system, textures, maps, and a few technical issues.