I'm sure I'm not the only one that has suffered through this.
The manual says that "by default, the Network Managemnt Card ignores DHCP offers that do not encapsulate the APC cookie in DHCP option 43" and then proceeds to explain how to disable that requirement in the web interface. Then it gives several examples of alternate ways to configure an IP without the web interface.
I tried them all but they didn't work. Yeah, so, turns out they didn't work because the system had grabbed a DHCP no problem, without the cookie.
So, the APC NIC does NOT actually require option 43 to be set on your DHCP server.