Tom,

that's right. First of all the X1 can't assign any reverb to other outputs but 1+2. And other settings are not anymore functioning once you use a different output assignment than standard.
Did you notice also that even the headphone output changes. That must be really a bug!!

It is very unfinished feature of the X1. It should be repaired in a future upgrade of the OS. (Hopefully coming soon!)

Marc