I think you probably want a right-draw traverse rod. Try continentalwindowfashions.com. for them. They have both the traditional white metal ones and decorative ones that look like the wood or metal pole rods. Yes, you will need at least one support for that span. Traverse rods allow for that because of the way the carriers function. Your drapery will have to have pins in the top to hook into the carriers, but I am guessing if you are doing sheers you will easily find them with pleated tops, into which the drapery pins go very easily.

You will love the function and the high end look you will achieve...if you like the look of rings some come with that accent too!....check out Halfpricedrapes.com for your drapery linen panels...they offer readymade in many lengths and some can be ordered in custom sizes...also will send you free samples I think up to ten free.

I really think dummy rods are strange looking. Curtains are supposed to cover windows...dummy rods throw out the pretense of that. I’d use a full rod and thick drapes that would look like they could fully cover the window. I remember a designer I worked with once told me things needed to look authentic and make sense. Dummy rods do neither.

Here’s a pic! I’ve thought about doing roller shades on the bottom rectangular section and leave the arches at the top open. For curtains, I was planning to mount them above the arch.