Jeff,
It works here. I suspect that you have the wrong box checked on the Door Size Settings dialogue. You will notice that as you change the checked selection in the "Set as Nominal" section the dimension marker display will change to match.
HTH
Erich
AC 19 6006 & AC 20
Mac OS 10.11.5
15" Retina MacBook Pro 2.6
27" iMac Retina 5K