Norton spun off the company UAV engines. Their website is here:
http://www.uavenginesltd.co.uk/
Also, a quote from their site:
"Please note that UEL do not supply engines for powering manned aircraft (or any other applications.)"
Having had some experience in the rotary wing UAV field with that engine, I wouldn't argue with their statement.
There was a recent article in one of the US homebuilding magazines that compared 4 RV8's. Two had rotaries and two had Lycosaurus engines. The main differences that I could see were:
1) the rotaries were thirstier
2) the rotaries were louder.
This agrees with my personal experience. My ears are still ringing 7 years later.
-- IFMU