I have a 2017 Rockwood a213hw. I loved the idea of covering the ceiling lights and tried the original model posted some time ago. I just made messes of heating and molding the plastic. I ended up purchasing Avery Clear Easy View durable plastic dividers. It's perfect becasuse it's very flexible yet not flimsy.
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I measured a ceiling light and cut a sheet, allowing for plenty of overlap. You can always trim it down before adding the material.
I had to cut material twice because I didn't leave enough material to roll the edges the first go.
I used spray adhesive to adhere the material to the plastic. Then I rolled the edges and used a small brush to run a thin line of glue to glue the edges down. When I make more (love to change colors and ambience), I will try rolling the edges before adhering the material to the plastic. That may be easier.
I used velcro pieces to attach the shades over the lights. The light switch is still accessible.