Any recommendations as to cleaning the retractable cover .? My efforts with a proprietory spray left streaky residue Thanks in advance

What spray did you use? First thought is it was probably too concentrated but let me know what you have used. And also what media you used? As in clean microfibre cloth?

I clean mine with a light APC mix and a soft leather brush.

Let it dry and using a cloth gently apply some 303.

Interior cleaners are generally similar chemistry as APCs but much lighter so it might be more efficient/gentler to get an interior product. Some of them also have aspects like antimicrobial or antistatic elements which will help with dust and cleanliness not needed externally so they can be good for more passenger-based areas.

303 is a decent consumer product been around for years. Anything that has UV-protectors in will basically work to stop sun fade while not being all shiny and greasy is good for places like dash and luggage cover.

Still not heard from OP - @Northernskoda123 did you resolve your issue?