Is the cord on the wall under the windows supposed to be taut to the wall or with some extra length? Also, it appears the rings are hooked only to the lining on the originals and not throught the facing? This seems odd and I want to be sure this is correct. I would think the rings should catch the facing as well
The elastic cord (?) is held very taut so as to keep the curtain tightly in place.
I'm not sure what type of channel your unit has to retain the curtains in place but those nylon attachments are held taut and, when finish, give the curtain a nice ‘tucked look’.
As I remembered it, it attached to the backing in such a way as not to show thru the front of the curtain's material~
Good luck on your project. It’ll make your interior's appearance look fresh ~!
I hope I understood your question correctly and, was able to offer some insight.