Hi Nancy,
The "Gleeful Glamper" here! I LOVE making a variety of window coverings and decor to go with many of our trips. I've made decor themes that include the desert, wine country, the alps, the Southwest, and more. Most times I go with traditional "cafe curtains" but my last effort included a flat hanging panel (much like Roman shades) that I just roll up and tie when I want to. I love the fabric so much that I usually keep the panels hanging over the
windows. On the outer sides of the rod and rod holder I put up traditional panels done in the style of "cafe curtains".
I'm sorry I cannot find my photos of the panels but you can use your imagination. (My trailer is stored 1 hour from my home so it's not easy to go there to take a photo.) Here is a photo of one of my other window treatments. In it you can see the side curtain panels. In the center, where you see the
light curtains, I hang a panel. At the top of the panel in the two corners I sew some ribbon lengths that are used to tie up the rolled up curtain panel. I see no reason to fiddle with the usual ropes and rings used for traditional "Roman Shades" in such a small space.
To see more of my decor postings just go to the "Search" button above, go to the bottom of the drop-down menu where it says "Google Search" and enter "Gilda decor", "Gilda window coverings" or Gilda curtains. Private message me or we can interact on the forum, whichever you prefer.
Please post a photo of your interior "curve" so I can see what you are dealing with.