Upgrading a Cyberoam OS to Sophos

Hi everyone, 


Please kindly help me out on this upgrade issue, I am upgraging a Cyberoam OS is a 10.04.2 build 527 version, appliance key C18213221192-ZV32DQ and model number CR100iNG to a 10.6 version and finally to Sophos but the final upgrade to a Sophos is not responding after I upload and boot the upgrade agent on the Cyberoam appliance. Please how do I go about the upgrade to Sophos. Thanks