Upps I forgot to give you a most quicker and less problematic answer (and you will get the same dancing mat/pad "error" in epsxe, fpse, psemupro, pscx, etc etc )...
If you are playing over a psx dance pad/mat and you use DirectPad, or anything else that can do psx pads to get in the PC working... you just had to think that when you pull a direction, the joystick only shows that single direction, for example, when you pull the joystick right, the direction your car/plane/caracter/whatever-else-you-think goes is right, but at the same time he can't go left cause your are pulling joystick right !! (with this, I want to say that only the first direction that is being pulled its the direction that works and if you are pulling two direct. at the same time, when you release the working one the another direct. goes working) ...so... whats the solution? its simple..., just take the joystick directions as single buttons (they can be pushed all at the same time) ... one button for up, another for left, another right and another down.
Well with DirectPad (or Similar) you can do this by setting the "Controler Type" menu to "Left Analog" . Then the directions are also set to buttons 13 to 17 or numbers around that
Byez to everybody and sorry if someone doesn't understand my english (poor english i had
PD: Smileys/Smilies suxx a lot