It sounds like you have already uninstalled version 1.1.......if this is so then those original drummers probably got uninstalled as well.
The Sonoma gang should be roaming by soon to help you. I think you might have to go through the following instructions to get this worked out:
http://www.sonomawireworks.com/guide/index.php/Will_RiffWorks_1.1_drummers_work_in_RiffWorks_Standard%3FIf RiffWorks Version 1.1 is uninstalled then this is probably why the Line 6 downloads are not working as they were meant to see version 1.1 (I suppose and am guessing here) and not version 2.
Sorry I can't give ya any better help....good luck.
BTW.....if you still have version 1.1 installed and lost the drummers installing version II .....well....like I said...good luck

Keep an eye out as you should be seeing one or two from Sonoma soon.