wmb, are you running x64 or x32? I am in x64 and the Sonar compatability check box is not available in 6.3.1 and the plugins won't operate although they do show up on the screen, the gain reduction needles odn't move on the fairchild.
So it may be either X1 x64 or the fact that I am running Win7x64 that is the compatability issue.