...from the pics I have seen, it looks to me that if you are already running the ProISL/USB solution, the module you have is redundant, as the fiber cable can be seen to input directly into the DD. That is, the module that plugs into the dac currently.
You would still need the small external (5v) converter for USB=>Fiber (then fiber into "hardwired" SFP in DD).
If the above is correct, the topic of a redundant module has not been mentioned, that I recall.
So, existing power base continues to power your dac. DD has its own internal power supply, so you'll need a cable there.
DD "Super Computer" does the crunching and outputs basic info via optical connection to dac. Dac does the dac thing and outputs to your pre/amp per existing.
That's how it looks to me. It had been mentioned (to me) that all of the DD modules were the same, except casework, but the content on the site differentiates between a linear and SM ps by model hierarchy, which makes more sense to me.
Anxiously awaiting more info from MSB honchos...and a demo!