Hey Toan, did you make that with version 2005 or 2008?, I've been plying with this today with 2005 and I'm having a time to get it to work, I find it difficult to place the risers in thr right location as far as being in the center of the middle stair flight, all the streching and editting I find it difficult for my taste, maybe I need lots of practice with stairs.
George