Instructions
Copy and paste the "Baseball Stars Professional" ROM file into the "Roms" sub-folder of the "MAME32" folder.
Open MAME32 by double-clicking the MAME32 icon in the main "MAME32" folder.
Enter "Baseball Stars Professional" in the white box at the top-right corner of the MAME32 window. Right-click on "Baseball Stars Professional" in the middle pane of the MAME32 window. Select "Audit" and "OK."
Right-click "Baseball Stars Professional" again and select "Play." "Baseball Stars Professional" will now start.