Well, marthas_ear, since you asked....
The cover:
I got a 16x40 roll of blue bubbles from poolandspawarehouse.com, it doesn't say but I assume it's 8mil. The longest straight side of the pool is 37'. Cross-wise, the shallow end maxes out at 23' but the deep end is narrow, 10'-12'. So today I laid out the cover along the long side and cut to fit, which left about a 7x15 trapezoidal section not covered in the shallow end. Trimmed a bit from the biggest leftover scrap to put there, and now the surface is mostly covered. If the scrap is snugged up against the big piece, there's maybe a 3x10 curvy section not covered. Actually it looks like the scrap is going to sort of float around in that section, and I didn't feel like trying to piece together enough to completely cover it. I still have another largish scrap so if I get inspired some day I could fill it in.
(Just looking at it, next time around I might prefer a 12' wide roll which would produce two more moderate-size pieces, instead of one big one with a bitty scrap. I haven't actually tried hauling the cover out yet, but just looking at the 16' makes me wonder how manageable that job will be. The cover is only 30 pounds dry, but it might not be a one-person job just because it's big. No room for a reel either.)
The cleaner:
The Polaris hose is about in the middle of the long wall. It ran in stealth mode (undercover

) for a couple hours this afternoon, and it looked like everything was hunky-dory. The Polaris has a sweet tooth--that is, it tends to snuggle up against the wedding-cake steps in the shallow end, and that's where the semi-open section with the free-floating scrap is. So I was a little concerned about whether this loose piece of cover and the Polaris would be any trouble. I checked on it a few times, shooed the Polaris away from the steps just so it would run around more, and it was all fine.
Now, if I had oriented the cover sections the other way, so the hose could bob up between sections, I could see that might be a problem. And maybe if the cleaner decided to climb the wall right between the sections and somehow ended up on top, that could be an issue. But for now it all looks good.
--paulr