I want to bump this topic here. http://www.cubase.net/phpbb2/viewtopic.php?p=943198&sid=4979f8bebdcf6f5056be11dbf889f76d
Freezing all instrument/Instrument Rack instruments with one click would be very helpful for saving CPU. Its a great feature that would save a lot of time, and it looks like several other users would appreciate it.