I am comfortable that addresses have been set properly.
Even the' dumbest little hub' these days is a switching hub. (I keep an old 10 base-T relic around for when I need a truly dumb hub) If the board is not configured to the same subnet as your PC, the packets will not get routed and Wireshark will not see them. The fact that Tx is flashing every few seconds would tend to indicate that packets are going out on the wire.
What about the reset switch?
I'll look into that. There is one on the schematic. I'll go grab a board and check it out.