Ours are outside mount because our windows aren't deep enough for inside mount. Before you put too much energy into inside or outside mount, might want to check if inside mount is possible (I imagine it is for most people, we have unusually shallow windows). Outside mount looks fine.

Yes we start the shade between the ceiling and the top frame, about halfway between them, and they are exactly the width of the outside window sill. We used Rockville Interiors.

Inside

Do you hang your Roman shades on the inside of the frame or the outside? My windows are wider than they are long, and I'm not sure which would look best. I've considered hanging the shades slightly above the frame to give the illusion of more height and help balance out the horizontal windows, but I can't quite visualize the end result. Would appreciate input from people with experience.