First of all, use a few pieces of moulding that might be chipped, or that you can spare. These will be your pieces that you should use throughout your whole project to check your sanity, or to be your guide as to WHAT kind of cur and angle that you will make. You have surprised me that you do indeed have a Compound mitre saw. Also, I am hoping that you are making right angle cuts, inside or outside doesn't mattere for right now.
Now try a 33.5 degree angle cut by setting the saw at 33.5 and TILTING THE SAW (that's what makes it a Compound). Do just the opposite side of the 33.5 degree in order to make the opposing angle. That should get you started as to the logic for the crown moulding cuts.
I'll be back to answer any more of your question Wednesday morning.
Hope I helped.
i have a compound radial arm saw and still cant get the angles right, please explain, inner & outer.