Oh my. Questions questions ;D
Rather than try to answer one-by-one, let me come at thngs from a different direction, by way of explanation.
Windows networking protocols are extremely chatty. The protocols were defined in the early 1980’s, before the TCP/IP networking standards came to the world of PC’s. Back in those early days, the protocols were kept simple. The basic principle was that each machine kept track of what was on the LAN. To have that happen, each machine would broadcast it’s name and capabilities to the LAN as a whole, and listen for the broadcast of that same information from all other machines. Then each machine would have the equivalent of a sticky note collection, saying things like “machine adam12 is at address 00:12:34:56:78:9a and has a printer”. So when somebody needed to print, guess who gets contacted: adam12.
The TCP/IP came along, and the old protocol got adapted to fit in the “new” Internet way of doing things. A LAN is roughly the equivalent of an address block (192.168.1.0 thru 192.168.1.255, for example). A broadcast address is always the highest address in that range (192.168.1.255).
Since TCP/IP gets used for a lot of different things, the old networking protocols needed some way of making sure that when they were “talking shop” they were talking to the right place. In TCP/IP terms, that place is a port number. Windows networking, given its variety, got a bunch of port numbers assigned to it by the keeper of such numbers (iana.org). Those ports are 135, 137, 138, 139, and 445. Each one has a different purpose, matching up with the original protocol.
Port 137 is the “name” service. In the old days, the broadcast would be “Hi, I’m adam12 at 00:12:34:56:78:9a”, in the new terms that becomes “Hi, I’m adam12 at 192.168.1.3” sent to port 137 (it’s a name) and a broadcast (send to 192.168.1.255). Windows however still has it’s sticky note collection, just some different bits. Every machine is still doing it’s broadcast, just like the old days. It’s just TCP/IP stuff now, in place of the original raw ethernet packets.
Microsoft, in their wisdom, have all Windows machines set by default to presume all machines want to talk to all other machines. If you share files and printers between machines, then it’s these Windows networking protocols that are doing the work. If you don’t, then you can turn off the Windows networking, and not miss it.
I opened CFP, and in My Network Zones I found a “Loopback zone” (127.0.0.1/255.0.0.0) and an “Intel(R) 82562V-2 10/100 Network Connection - Packet Scheduler Miniport” (192.168.1.7 255.255255.0). I assume the latter is “the zone name for my LAN” to which I should add the single IP address of 192.168.1.255? Right?
Yes, that sounds like the right place. But, as I read your description, the broadcast address is already included. The 192.168.1.7/255.255.255.0 is just another way of writing the range of 192.168.1.0 thru 192.168.1.255. It's called a "netmask notation". That you're getting CFP log messages says to me that there is a rule blocking the packets. The question then is, where's the rule doing the blocking.
The easy way to check that, is the CFP Config Reporting Script. It’s described in a sticky post at the top of this forum page. If you would run the script (for firewall rules only, please. The script can produce huge amounts of output otherwise), and post the report here, then I can see what the rules are, and what might be the problem.