Alright, I re-read what Graf Zahl told me and what the exact issue is is that Keen works fine, but you can no longer transfer his code pointer to an enemy.
That being so I was looking for an ACS based solution, but now that I'm typing this, I have one other trick with Bex that I'd like to try out. I just though, if I simply lend one of the enemy's action frames to Keen, thus keeping Keen as Keen, Death Frame and all, then everything should transfer and work, the only down side then will be that I can only have one enemy type that carries the Keen Code Pointer which kind of goes against my master plan.
Oh well, if I can just have one Keen that walks, attacks, and has an association with Tag 666, then I'll get by, but having the ability to use ACS in relation to any enemy on any level would rock. Odamex is really awesome till it comes to working with weapons and enemies, then it's like 1999 all over again, still yet, I'm having fun trying to make Bex do neat things, I just wish it wasn't broken. :)