Hidden doors

[Fatmice]

Is there a way to rig the triggers so that a hidden door reverts to being hidden after your sim is done using it?

What about removing the keystone from the keystone panel afterward?  I don't see such an option.  Is there a clever trick to do just that?

I found a neat trick on the official sim forum http://www.thesims3.com/contentDetail.html?contentId=126493