Still puzzling over my snails though. Here's two of them, top and bottom, both removed from the walls of the house in a rural garden:
Snail 1 - 10mm wide, 7 mm high - 5+ whorls, large umbilicus, no obvious lip, not keeled. Dark, blotchiness showing through towards centre particularly. I don't think I'd call this glossy, waxy or particularly translucent? But if I follow the key for the Helicoidea, I end up at (a small) Trochulus striolatus, which I think has a lip. If it is glossy, then perhaps this is Oxychilus cellarius? But it doesn't really look glossy enough?
Snail 2 might be the same thing but paler. I don't know how variable shell colour is. Size just slightly smaller at about 9mm wide, 6 mm high.
Any suggestions gratefully received!