Very nice improvement in brushwork and scripting. Outside area is really well done. I didn't like hard to reach ogres and snipers raining fire from above. It's hard to react to them and thus it feels cheap.
I looked for entrance into the castle for a few minutes. I visited the cave with the zombies, but because it was a secret I didn't figure out that the path was there. I think that the main way through the map shouldn't go through the mandatory secret areas. I feel that the convention 'secret = optional' is too strong to play around with.
Also in the dining room the floor gave in when monster stepped on it, which was hilarious but spoiled the pretty cool trap (btw cellar is very well done, the scrag and the grenade secret were great).
You can check my demo (I cut the middle part where I look for the secret door): http://mgrankin.xyz/quake/fireplace.7z