I'm trying to get our WAN sites connected over ADSL configured to
correctly pass ZEN traffic and would like to know which ports need to be
opened for broadcast.

I have compiled a complete list of ports from the ZEN documentation (see
below) but can only find the udp ports 67 and 68 need to be broadcast to
find the PXE server. Are all the remaining ports only unicast once the ZEN
servers have been identified?

* UDP Ports 67, 68 and 4011
* UDP Port 69 and 360
* UDP Port 111
* UDP Port 18753
* TCP Ports 1761 and 1762
* TCP Port 389
* TCP Ports 80 and 443