Oktagon ROM part1 + part2 attached.
Also did the DiskSpeed run on Oktagon, same disk, and FastRAM with Supra 500RX.
(Standard A500, Supra 500RX, Grandslam expansion box, Oktagon 2008, Seagate Barracuda ST32550M)
http://peo.yliniemi.se/amiga/HD/DiskSpeed-Oktagon.txt
(about half the speed of Trifecta)