Gave this a play through yesterday and enjoyed it a lot, but had a few issues with it.
About 1.5 hours in the game crashed out completely and froze KeeperFX (using a recent build). Undeterred I loaded up a save from a few minutes prior and had no further crashes.
Also had to move quick to secure the eastern gem tile, as Green kept making a beeline for it despite having 3 tiles all to his own. I had to restart two or three times as I was too slow to do that.
Unlike YourMaster above I found the scavenger room unproductive initially. That may be because my entire army consisted solely of 12 bile demons and 12 dragons (couldn't see how to get a torture room or barracks for other minions to start with, and didn't want to take on warlocks or anything else). I managed to coax three dragons away from Blue keeper, but that was it! This left me with 27 creatures, less than either Green (28) or Blue (35). I gambled on Green having other rooms with which to attract different creatures, and hopefully a prison too. Although my army was cut down to 16/17 creatures, we managed to defeat Green and I took over his prison, torture room and barracks and was able to attract some mistresses and orcs to get back to portal max of 24. And these were slightly more productive in the scavenger room meaning I could get up to around 32 creatures total before capturing and converting heroes from what was left of the hero keeps. Blue stood no chance as I'd drained him of his mistresses, and outnumbered him with additional heroes/skeletons. There was at least two phases of significant frame skipping required - one just for building up the cash via workshop to fund the scavenging, and another to train everything up.
I'd say this is a solid 7/10 map when compared to Deeper Dungeons.