I have this board and I see that "TeleTubby666" also has this board. I was able to update the OROM to 11.6.1702 and run RST 11.7.4.1001
Question, is it possible to update to OROM 12.7.0.1936 and use RST 12.8.4.1000 with this board?
Probably yes.
When TeleTubby666 made his BIOS modding, there were neiter Intel RST(e) Drivers nor Intel RAID ROMs of the v12.x.x.xxxx series available.
I’ll give it a try.
My P7P55D Deluxe system has programs on it already and it is a single SSD
I have done RAID0 with two regular drives and SSD’s, but been reading too many horror stories about arrays dying so I went back to just single for now.
I know most here have the two SSD set up; I’m the minority here with the single SSD. But trying out to help too. 
Installed the OROM 12.7.0.1936 in to my P7P55D Deluxe. No issues so far. I’ll report back in a month and let everyone know if I had any issues. I will also post for the P8P67 Pro I did as well.
Originally I had
OROM - 11.6.0.1702
RST - 11.7.4.1001
BIOS - RAID
Single SSD
We can add this to the “success” mods listing.
Vendor Product - Asus P7P55D Deluxe
Sort - MB
Chipset/SB - Intel P55
Inserted BIOS Modules - OROM 12.7.0.1936 with RST 12.8.4.1000
Results - Success
Remarks - no so far
User name - denaba
On this system there a single SSD; 120 GB SanDisk Xtreme along with 4 regular hard drives. Here are the comparison between the OROM 11.6.0.1702 and the 12.7.0.1936
