Our situation is a little different. We are installing new cherry (light/medium stain) cabinets ceiling height with 5" crown with same finish. We intend to put 5" crown in dining area of room (kitchen/dining area is 20x12 and each are is approx. 10x12). We plan to paint dining area crown white. Both the custom cabinet rep and my son, who has many years of remodeling experience, claim this is commonly done. In fact, I have a 4' break in kitchen crown over a door that will also have the white painted crown. That seemed odd to me but both assured me this is common. I purchased raw crown from cabinet company for dining area to assure that the profile matches which is important. My son and cabinet rep had different opinions about joining the painted and stained crown. The cabinet will install the cabinets and stained crown and my son the rest of the crown. The cabinet rep suggested mitering the corners but my son said he was old school and would use coping saw to join the crown. I hope this is helpful. Best wishes

The proper way is to cut a miter for an outside corner, with the long point being the length to where you want the moulding to end (about 1/8 short of the end of the wall), then cut other piece just like you would do if turning the corner. This piece is now cut just long enough to return to the wall. It is referred to in the trade as returning a piece on itself, and is how to end all profiled material in this situation.

sorry. I meant to say Sherwin William SW not BM in above post

ffjunk, of course it's a personal choice, but thought I should add, we have a situation similar to yours, with a pass-through window between painted cabinets, as well as a pocket door between a cabinet and a cabinet pantry. Our cabinet crown molding, and our whole house crown molding are the same heights, but different cuts, so the choice was easier for us - keep the same crown molding throughout the kitchen, though it is open concept. We are using stop blocks at the pocket door crown as the pantry is a stained along with the crown molding above it, and the cabinet adjacent is painted, along with the crown above that. The trim around the door will be painted the same as the cabinet/cabinet crown molding. Our ceilings are 9'. We are also using a stop block where the whole house crown meets the kitchen cabinetry crown - it would be very difficult to both cope and scribe the crowns to match and we prefer the stop blocks. I don't have photos as we are still in the midst of remodeling and our cabinet maker has yet to bring and install the stop blocks.