Answer to your last question:It's a deliberate feature. It's emulating something called 'creep' that conventional autos have. It''s actually quite neat when you are just tootling around a carpark or manouvering (saves having to balance clutch and accelerator). Unfortunately it seems to have two creep speeds. 10mph and 20mph. The latter can be quite annoying in queues or when turning into a side road if you're an engine braker like me
The Digression:
I'm sorry for my part in that digression, I didn't intend it to become an MT v. AT hate thread but I do tend to evangelise about CVTs a bit.
I think it's because I'm a recent AT user. Until Summer '05 I'd only ever driven a manual and had 17 years under my belt. The AT (A Chevy Aveo) was annoying when it hunted going up hills and I detest torque convertors but I loved not having to bother with a clutch or gear lever.
When I got back home I decided to do some research and found out that CVT was coming of age. One drive and I was hooked. I've never been a petrol head and just want to get from A to B efficiently and easily.