The Line6 version 2 is different from the Standard version 2 in a couple ways. The Line6 version is tied to the Line6 hardware (i.e. GuitarPort) for authentication, and does not have the "Amp" tab in the hardware effects to enable an amp VST, nor the extra Amplitube Live 2 that comes with the Standard Version.
The Standard version will work with most ASIO hardware (including the Line6 modelers, but also things like Stealthplug, JamLab, Mbox, etc.) but not the other way around. It also comes with the Sonoma gang for direct support!

To find the exact version you have, you can click on the "RW" logo in the upper right corner of RiffWorks, and it will display the credits and version where the layers normally go.
J.J.