By cascading two RM's as master/slave, you get 64 + 4 tracks via firewire (Capture) on master RM, but you have to decide, which tracks you want to record. Generally said master RM (FOH) feeds channels 1-32 and slave RM (stagebox) feeds channels 34-36. If you think of some kind of stagebox mode, you may only want to record tracks 34-64 (the inputs of slave RM on stage). You can also do the live mix on channels 34-64, but it is possible to "mirror" channels 34-64 to channels 1-32 by selecting "network" as their input source. This means that master RM's local inputs get muted. All outputs are anyway "merged", the slave's outputs mirror the master's outputs.
Of course this works with any combination of RM's and I think with the latest firmware it is now also possible to cascade two RM's and control them with the CS18AI. Just leave one RM32 at FOH and you are ready for anything! CS18 does not allow multitrack recording, as it is only a "controller". Cascading of SL and RM boards is not possible. That would be nice, but they are different beasts...
But why not keep SL32 at FOH? A SL32 also allows recording via firewire at FOH. As an alternative or additional source you can record from RM32 via firewire. There is two times 32 track recording possible with SL32 and RM32...
For these kind of games you do need an AVB switch. The MOTU does what it is supposed to do. You will also need a router.
Hope this helps.
