are you still using that hacky workaround for getting gates to work???
cause fang has a rather useful LUA gadget that could of some use for this..
its basically when a button is pressed, an animation gets run and then a replacement unit gets spawned in and the old one removed...
so you could have you gate run its anim at button push then get replaced with a opened version of the model. then when u hit close the shutting anim runs and the closed version gets spawned