Great questions Steve! Yes I always use a range finder and use it 2 ways, range objects as you settle into the stand..could be trees,edge of the grass, or a knob etc. I like Nikons range finders personally, but I still have a bushnell for back up. Furthest shot was 175,I put it in between the first 2 circles and pulled the trigger. Under 100 yds, if I remember right at 50 it hit about 2″ high, not a huge deal but you could adjust if you felt it was needed. I plunked a few practices at 200+ and the reticle was right on, but I needed to adjust for cross wind,easy during practice but not when the animal is in your sights. My goal this year is to learn windage and record bullet drift. You got me chomping at the bit to shoot my encore right now, but the bow and the new .270WSM have priority right now. Here is a link with some nice tips on setting up a omega scope.
http://www.nikonusa.com/fileuploads/pdfs/OMEGA_manual.pdf
Happy hunting!