I'm that type. I often check maps in the editor. Can't specify any mod or map though. But I checked that level you mentioned (bedrone) and HOLY S**T is it big or what? I've played it for hours and I've still not finished it.
Really cool effects.. and I wonder too how he did certain things. Never knew some of those things could be done in Duke3d. He seems to have some kind of stack effects (like in shadow warrior and blood) faked I guess, but nice anyway. But I must say that transparent water thing was the most impressive thing I've seen in duke ever. I thought I had figured out how he did it, but then I noticed you could shoot enemies through the water, and my theory fell through. Is it possible he has coded in some new effects (like transparent water and stacks) through the con files?