OK well here is a problem. I am on 9.1 and when I flashed the supersu zip, I get infinite boot animation screen. And I get this message in dmesg " (0)[83:hang_detect][Hang_Detect] hang_detect thread counts down 2147483647:2147483647, status 0." I am amazed that it was able to flash tbh. The newest one will stop and say its unsupported.Okay I see, so here is probably the quickest way of getting your unit fully customized (detailed instructions are in the OP):
1. Backup your current unit by means of a Memory Dump
2. Import the same memory dump back to the unit and ensure it works
3. Perform all tasks in OP starting from Memory Dump import but you can probably exclude importing "BOOT1" or "ROM1" as you have a working unit. Only import the large file 14Gb.
EDIT: ill just try to install your image here and see what happens. I thin I have already tried actually but it boot loops my device.