1st be sure you have mouse support enabled in your mame option, when your game starts up you hit the tab button and this brings up the menu go to 'input this game'. you go down to the dial and press enter which will make the field blank until you press a button or move a stick to assign it to that function. you'll need to move your mouse so it knows you want it to perform that function. I've noticed that the default on most games that use a dial is to share the function with joystick which causes a conflict and I have to go in and change it to just mouse function. After you have it set to mouse you go to the analog options and change the sensitivity to your liking. seems that every game has different physics so you'll be doing some testing for each game.