Lyn writes a check for $900 to Mac, who indorses the check in blank and transfers it

Question:

Lyn writes a check for $900 to Mac, who indorses the check in blank and transfers it to Nan. She presents the check to Omega Bank, the drawee bank, for payment. Omega does not honor the check. Is Lyn liable to Nan? Could Lyn be subject to criminal prosecution? Why or why not?