Originally Posted by demolition
Just tried it out in the 600 with a Vampire 2 board and still getting nak timeouts with Ethernet, just in case the CPU type would have an impact.
Vampire is not a real 68k CPU, and the hobbyist-way that the "team" approaches this task does not indicate that it will ever come close to a real 68k CPU. As much as I'd hope that FPGAs will some day be able to replace the ever-shrinking supply of 68k CPUs, Vampire takes the wrong approach (try&error simply doesn't work on this kind of task).
Ethernet on USB: Make sure it's an ASIX chip in your Ethernet adapter.