Obviously the S12 source command is one step. My S12 had an average of 10 steps for the source select commands and each one has to be assigned the proper port on the RP6. Multiply this by 10 zones and 12 sources and you can understand why it might take a while to set it up. I do not use the internal video switch which adds to the complexity. All my video is switched through a matrix Component/composite and coax digital switcher.
With two theaters in my system there are extra steps for the video sources that are dedicated and exclusive to those theater receivers. Believe me, the number of steps add up real fast.
The next one I do I want to try it with RS232. It makes sense seeing as nearly everything I use is RS232 controllable. It would also prevent I/R traffic jams from two zones trying to make changes at the same time. RS232 is lightning speed compared to I/R, even with the trigger commands in the RP6.
I'd be interested in knowing if anyone has had experience donig an Elan S12 with RS232 and how it worked out.