Double Twelve is definitely one of the easier games. It's pretty leisurely paced and is fairly easy to beat. Some folks don't wanna have their brains bent at 8:00 in the morning while they're sipping their coffee, so this should fit the bill.
Biggest new addition is a guest-account. The game-login screen will now have an button that'll let you play as a guest, which should make things a little nicer for folks who wanna try out the puzzles. Guests won't have their scores recorded and will get a different puzzle from the registered players (so you can't use the guest login to cheat), but it's otherwise the same.
So give it a try and let me know if it's all working. If the guest-login thing works, I'll retrofit it into all of the other puzzles.