I have been experimenting with support material in Slic3r 1.0.1. This particular shape is creating difficulties.
I have had success using default settings and interface layers = 1 on simpler shapes. The support inside the ring is difficult to remove without cracking the ring. The support under the ring is too difficult to remove.
Any thoughts on how to improve the supports without generating them in a different program?
Is there a reason you aren’t flipping the ring 90 degrees so it is flat on the print bed?
Because he said he was experimenting with support material. 
Kisslicer, Cura, and Meshmixer all create varying types of support…I’ve been happiest with Cura, but could see how a printer with better support for retraction would have excellent luck with Meshmixer.
@Josh_Ajima , like @Mike_Miller said, this piece is just to try support. I started with an inverted demisphere and then with just the lower demiring. This is level 3. I think level 4 might include an inverted cone as well.
Sorry @Mike_Miller @Matt_Harrington , it was a reflex. Whenever students approach me about a support issue, I always ask them to first check if a change in orientation will fix the problem.
@Matt_Harrington
Print settings --> Advanced --> Support Material
Possible to reduce extrusion width for support material to a minimum thus making removal easier. Only tried this once but it did seem worth further experimentation.
@Josh_Ajima , I’ll give that a try but the support already releases cleanly under the arch. The problem seems to be when the edges of the support run parallel to a permanent surface.
In the picture, you can see that the leg of the arch under the ring is encompassed by support which is wider than the structure as a whole. I suspect that improving this would mean either adapting the shape for easier printing or changing the shape of the support. Perhaps I should give slic3r 1.1 a try.
