Okay I looked at your Image Builder script more carefully and looks like you're also building from the HP October 2012 release set, and you're already including vmware-fdm, which is great. So are you just stalling on "Running vmware-fdm start..."? And if so, for how long?
I also noticed for some reason you're explicitly overriding the be2net driver. As I mentioned if you look at what HP is bundling in their custom images of ESXi 5.1, you'll notice they are no longer including be2net and lpfc820 used by the HP blade server's FlexFabric/Flex10 adapters:
http://h18004.www1.hp.com/products/servers/software/vmware-esxi/driver_version.html
You'll also see in their HP Virtual Connectivity Stream guide (HP Passport login required) they recommend using the VMware inbox drivers for be2net/lpfc820 under ESXi 5.1. But they also recommend the latest firmware available to the FlexFabric/Flex10 adapters, which even exceeds the SPP 2012.10 set:
So I'm curious why you're doing this for ben2et at this point? Are you pairing with a specific firmware version installed on your BL460c G7?