Oh, don't worry about it being dead.
I'm a Forum Moderator there myself, so feel free to keep this thing chugging along too. Haha.
Right now the website is down, so you may have to wait a bit. :x
osu! doesn't have the same difficulty in StepMania in terms of actual rhythm. The hard part is where you have to use hand-eye coordination to accurately move and whatnot.
1. I have a friend who plays semi-decently on touchpad. The best experiences are with a mouse or a tablet though. A USB mouse can suffice, if you want. The touchpad works, but you'll have to move your finger a lot (It might hurt).
2. This game is based off Elite Beat Agents and Osu! Tatakae! Ouendan!, both iNiS games from the DS. If you know how to play those games, then you can do pretty well off here. Play songs you know well first. If you can't seem to move that fast, try increasing Mouse Sensitivity in the Options. This way the cursor speed will be multiplied by what you specified. If you can't play well with tapping, try using the Z/X Keys (Or whatever keys you mapped those for). Finally, since it's a rhythm game, most maps have a pattern you can muster through. (Like if the song has a straight quarter beat or something, blah blah).
Wall of text. :<