I have that map on my old PC. Too bad it's dead and I couldn't get it running again.
The map is called something like: DM-Lift Down.
I sent it to Hermskii years ago as a possible map for Curious George's Redeemer Insanity. I thought it might make an interesting change of pace for the server. But Herm didn't feel that it passed muster. I too have been totally unable to find it. I most likely got it at Nali City.
I also cannot find a map called DM-Redemption any more. But that may be because someone else later made a map with that exact same name. And the new version may have overwritten the original when it was uploaded onto Nali City, and elsewhere. The new version is a church. The old version I liked was just a big rectangular field surrounded by a wall. There were many shell holes to hide in, and some blown up buildings inside the walled area to hide in. There was also a tunnel that ran the length of the map, and two tunnels that divided the length into thirds, that ran across the width of the map. It was called redemption, because the only weapon you could find anywhere to pick up was a redeemer. And there was one in every shell hole, and lots more scattered about in the ruined buildings and in the tunnels. You could carry a maximum of two redeemers, so you had to keep moving.
It was my first introduction to a simulated redeemer arena of sorts. When I discovered CG I was already a bit familiar with what I needed to do to play the mod. Although playing in the small and enclosed maps that ran on CG meant a lot of learning.
I sent DM-Redemption to Herm as well, but it failed to make it onto the rotation too.