Push the cash-credit button, it should lite up. Then insert a dollar into the bill validator. It should now give you 2 credits if BV is set to 50 cent denom. You will have to use a set15 to set BV to .25 After that you should get 4 credits instead of 2. If this does not work you have to check some other settings (like 5_0 and 8_0) As long as the cash-credit button remains lit you should get credits when you win instead of paying quarters also.