Also remember that you have to use A-F on the B&K. The RTI driver is made to control codeset 11-16 or A-F. Which means you cannot control a B&K party zone with the driver if that zone is for example codeset 23.
So the 1st CT unit will be codeset 11-16 and the 2nd unit will be 11-13. Both will have a seperate driver with 2 RS232 outputs out of the XP8. If you're running out of RS232 ports you should be able to control via ethernet. Just make sure the CT units have the latest firmware updates.
Good luck!
"Just when I thought you couldn't possibly be any dumber, you go and do something like this... and totally redeem yourself!"
