I have copied over silverhead's response to your previous post, as it is the correct answer:
"The Line 6 Edition of Riffworks is no longer being updated and does not officially support Windows Vista, Windows 7, Snow Leopard, or Lion.
you have a few options available:
A free version can be downloaded here:
The Standard version is not free:
Sonomahas provided a discounted crossgrade for Line 6 Edition owners:
RiffWorksVersion 1 owners receive $70 off, making RiffWorks $59.
RiffWorks Line 6 Edition Version 2 owners receive $100 off, making RiffWorks $29.
Your personal Riffworks data files are fully compatible. Simply copy those files to your new computer to use with your new Riffworks installation as you would with personal data files for any other application.
although no longer supported, you can download the line6 edition here: http://line6.com/software/
byselecting windows XP as your operating system."