Bizarrely, I had a password/login error on my up to date version yesterday. It was a pain as i couldn't play so i thought i'd just uninstall, redownload and reinstall. The bad news being it simply won't install... Its downloaded (i've done it 4 times now to check) but when i double click i get the egg timer and nothing else happens even if i leave it for an hour or two. It also tends to messup my system.
I've turned off firewalls, antivirus etc... I seem to remember it taking a while to start the installation last time but maybe 10 mins or so.