DIRECT ANSWER
Bind the bow thruster to its own centered axis or two buttons, verify direction while nearly stopped, and use short inputs during docking.
Setup
Treat the thruster as a separate control surface.
- Use a dedicated axis or left/right buttons
- Confirm center produces zero command
- Invert the axis if port and starboard are reversed
- Remove duplicate bindings on unused devices
- Test at low speed in open water
Operating limit
A bow thruster is most useful at low forward speed. It is an aid for lateral positioning, not a replacement for planning momentum and rudder response.