Custom procedure for slab, stair, custom model events

What I mean is I want the rotation of stairs with my custom model but it doesn't let me, it locks the model part when you use the stair. Now granted, yes I could in theory use custom model and try to do the rotation for stairs via procedure, but it's not the same as I'd like to have custom model for the inner, outer, and stair. 

I'd also like this for the other models sets as well.  

Can be a procedure with template or autoset, but it would be very handy.