As the other posters in here have eluded to, it needs to be redone. According to our tradition, only a male can do it, and only a rooster can be sacrificed. When it is up, it can not be altered until it New Years, or if you put it up wrong.
The xwm kab is thought to be a guardian spirit, like an guardian angel, who watches over not just the house but the family aswell. Therefore, in the olden days people who are going to go somewhere are asked not to look back at the house. If one does so, it is an indication to the xwm kab that that person is scared and so it will follow the person to protect him or her. Thus, that person will hear footsteps behind them. This is quite spooky, but it is not the intention of the xwm kab to scare.
The xwm kab is tolerant and different faiths can exist within the house it dwells. The only problem is that another xwm kab exists in the house. All male in our tradition has a xwm kab and can put it up when he moves out. However, when the male puts it up he can no longer come back and live with in his father's house if his father is still alive. This is because one cannot just put the xwm kab away without converting, and two xwb kabs cannot exist in one house. If they do, there will be conflict between the two, which translates into conflicts between father and son in our world.