You may not have an amount in box 12 ... state withholding is not always done most times because the distribution is not taxed by the state and as such the withholding is not needed.

If your state taxes personal income, then boxes 12, 13 and 14 *MUST* all have something in them. If your state does not tax personal income, then all three of those boxes *MUST* be left blank.

My own experience has been the same as @Critter#2.

Your custodian will determine whether to allow you to withdraw without state withholding, federal withholding, or neither.