I am not really familiar with VFD setup as I have only used servo spindles under Mach control. I think however you will need the spindle Step Pin set to 1 and the Dir set to 0. After that I am not quite sure as the documentation is basic (to put it politely
) for your BOB. Disabling the Chargepump via the jumpers and using Pin17 as the pin for OutPut 1 is my best guess.
Hood