I have begun preparing an update for this, but I'm not quite sure how close to the original Keen 2 I should try to get. All I've done at the moment is fix a few errors in the patch file and prevent the Scrubs from turning into Amptons (and killing Keen) when they reach a pole.
As you know, FITF has an enemy that can walk on walls and ceilings. The Scrubs in this mod are currently just walking on the floor, which means some levels had to be redesigned because the Scrubs can't climb walls and therefore can't carry Keen to where he needs to go. I would have to turn this mod into a source code mod to implement that, and I would have to redesign the levels to incorporate the Scrubs into the design. I'm not a good level designer, so I would need some help for this.
There are some other missing features as well, like the light switches and the instant game over when activating a Tantalus switch. These would also require source modding (I really don't want to write all that code in machine language and patch it into the game.) And of course the real ending is missing as well, but that should be relatively easy to add with patching alone.