Interior Projectile Performance?

I'm having some issues with projectile performance in one of my maps.

www.blockland.us/blockland/Media/00%20Development%20Screenshots/kitchenMulti.jpg

The map is a kitchen done on the scale of a lego man- so it's huge. Its also pretty complex in that you can get inside most of the cabinets and the refridgerator. But it's all portal'd off and I get 100+fps through out most of the map.
The problem is that in some parts of the map, the engine all but grinds to a halt when I shoot a projectile. Like if I stand in the hanging plant pot and shoot an arrow across the room, the engine bogs down until the arrow hits it's target. I've also noticed this problem on my other map although it's not as severe.

There are some complex bits of geometry like this: www.blockland.us/blockland/hinge.jpg , but they're all inside seperate zones and shouldn't be a problem. I tried deleting them and it didn't help.

I'm using TGE 1.3 and standard map2dif. I tried map2dif+ 0.96 but I got the "you dont have the correct artwork" error when i tried to launch the map.