Good news is that you already see cursor movement with the trackball.
1. Set "Track X Analog" to "Mouse X". (highlight, Enter, move trackball to the right or left)
2. Set the "Inc" and "Dec" to "none". (highlight, Enter, Esc)
- MAME uses these settings to turn joystick movements into simulated trackball movements.
3. Repeat steps 1 and 2 for Y-axis, but move the trackball forward or backward for "Mouse Y".
4. You may need to set the sensitivity or reverse an axis in the MAME "Analog Controls" menu.
If cursor movements are still erratic, check your Mouse settings in Windows.
Scott