Hi,
The crash is in the plug-in. Please, get in touch with IK Multimedia.
There were similar reports with the plug-in recently.
One of the reasons I switched from Amplitube to Guitar Rig was the general unreliability of the IK plugins.
Don’t get me wrong - I have most of their offerings, T-Racks, Sampletank, Amplitube and others, and they are excellent plugins, but they do randomly crash Cubase.
That is my experience with IK plugins, too, they have a habit of crashing (although for me it is mostly the instruments, the T-Racks plugins are quite reliable).
They usually do fix the crashes, though it might take some time. Always a good idea to update them regularly.