Do not use XHD Setting, set the BIOS like this
eXtreme Hard Drive ........................Disabled/Auto
PCH SATA Control Mode ..................... RAID
SATA Port0-3 Native Mode ( ............. Enabled
Then on the AHCI BIOS/RAID Screen, right before the IRQ Screen during post, hit Control + I to enter the Intel RAID ROM.
You should also connect your drives like this, sorry if I missed one I just used what you mentioned.
SATA3_0 for your OS
SATA2_2+3 for your RAID disks
BDROM on SATA2_4 or 5
Setup this RAID array after you have the Operating system installed, but use the settings I mention above now, just leave the RAID Disks alone until later. Once you have the OS installed then you can reboot and create your array, or create it in windows after installing the RST program. You will have to use GPT partitions instead of MBR for partitions larger than 2TB