how to remove static objects

[sllide]

If you mean first you have the wall then you pull a lever or something and then the wall is gone?

Well you need to use the model editor to be able to do that since you cannot turn a static object on and off. Only entities can be turned on and off. But there are already "some" secret walls it depends on what set you're using

Bummer.
I'm using mansionbase, maybe its possible to move the walls?