RTG version works great on my A4000, I thought it wasn't working at first as it was stuck on a grey screen for about 20-30 seconds but I guess it was just loading!
Once the menu came up it was fine and pretty smooth even though my A4000 is 040@40mhz (WarpEngine) and not an 060 like the readme says it requires, so I guess you can put 040 as the requirement but 060 as recommend.
I played the first couple of levels of Doom II and it really is playable on my setup. I'm using Picasso96 with my CV64/3D by the way.
Kudos on the port, any link to where we can find the TC's?