Raid config for S2600CW2 Server Board with FUP8X25S3HSDK 8x2.5 Hot Swap Drive Cage Kit in P4304XXMFEN2

I'm trying to install the S2600CW2 board in the P4304XXMFEN2 Server Chassis, using the 8x2.5 Hot Swap Drive Cage Kit FUP8x25S3HSDK, and the AXXCBL380HDHD mini-SAS cable(s).

Problem is the embedded Raid s/w ESRT2 and RSTe only see 4 drives of the for configuration purposes (i.e. I can configure to arrays of up to 4 drives each, but no more!).

Am I wiring it wrong? I have one of the AXXCBL380HDHD cables going from the board header SATA0-3 to the Hot Swap backplane connector Ports 0-3, and the other AXXCBL380HDHD cable going from the motherboard sSATA0-3 to the Hot Swap backplane connector Ports 4-7.

How can I combine all 8 drives into one array?

(By the way, the Server Configurator interactive Guide omits the requirement for the AXXCBL380HDHD cable)

Thanks. Any help would be appreciated.