Unfortunately, you haven't yet posted these drives in your compatibility sheet. However, I would really like to get this working with these drives if it's possible and want to share how far I got and get some engineering/technical feedback.
In short summary, the drives and capacities were recognized fine, disk array and logical drive were created successfully, synchronization process went through in full, but when that was over, I noticed no logical drive had mounted to my desktop nor was any logical drive showing up in Apple's Disk Utility.
I could not find any reported errors either.
I created an eventlog and saved out a subsysteminfo.html file as I've seen advised here on the forms and not sure how to attach here, but will be calling tech support to see what they can tell me by pointing them to this thread. In the meantime, any other tech support, thanks for looking over and helping me understand any thoughts as to why the logical drive didn't mount and what to try differently another time around as I think maybe I just missed a step or detail when I tried this the first time around per advice from a Promise tech support person by phone.
12TB drives recognized