Am I supposed to pay the amount on the form at the end of my completed tax return for Maryland: MY PERSONAL DECLARATION OF ESTIMATED TAX: Pay $540.00 by January 2018

Form 502DEP is for estimated income taxes for next year (2017) and are optional. TT/Maryland computed them up based on information in your 2016 return - usually when your tax withholding isn't enough to cover your taxes - to help prevent an underpayment of estimated tax for 2017.