Hello,
You should double check with Sonoma Wireworks to see if Riffworks is compatible with Snow Leopard. It's a little unclear right now.
www.sonomawireworks.com
Also, you may want to consider upgrading to Riffworks Standard from the Line 6 Edition. I believe we are running an upgrade special on that right now and the Standard version will be the version that Sonoma will continue to update from this point on.
Have I answered all of your questions?
Line6Miller