Hi,
I'm using Nokia Maps on E65 as well and have experienced some of the problems you describe.
Can't comment on 2) as I haven't used navigation in the UK yet. The routes I have used have seemed quite reasonable - and I can always take alternative route if I know it to work better, as the recalculations appear fast.
As for the 1), 3) and 4) I used to encounter these with the first version I installed. I uninstalled it on an occasion and installed the application again and the new version (v1.1 wk23 b04 OpenBit) has appeared much more reliable.
It would be nice if the software told when there is an update available or if the smart2go website would tell you the most recent version number. As of now, I haven't found any other way of finding out than downloading the installer and trying to install it.
-- Heikki