Peter, crown molding is difficult but not as bad as stairs can be. However, we can give you a little help on the crown. Go to Steve's Place at www2.fwi/~kruny/ for a lot of great info on inside and outside corners. For what it's worth, I like to bevel cut 2x4's to the same angle as the crown and a little smaller than the space that you would have behind the wall/ceiling corner under the crown when it was installed. Then you can screw the 2x4 into the studs and you don't have to be ultra-precise. When you actually put the crown up, you can nail anywhere and not worry about getting the nail in the stud. This really helps when you are trying to hold the crown in position exactly also.