I've tried and tried. It just won't work. Maybe I need to get a different firewall program. I'm working in Pro, added the features, made the firewall exceptions, have my network setting as "private," I've done everything. The host will be visible on the network, but logins time out or fail altogether.
Since writing my rant, I found HFS, which, though an OLD program, was stupid stupid easy to set up.
I also found Filebrowser, and though the config was way more of an asspain than it should have been, it's fucking awesome. I've even moved on to trying to get HTTPS running for external connections using Win-Acme, but it isn't going well.