Correct me if I'm wrong, but I should be able to link the property 'DrawnDate' to the current date, last saved date....something.

I go to file --> properties and I want to choose a value for the DrawnDate property, but nothing happens when I click the drop down arrow.  The window changes color, as if it's becoming the non-active window, but nothing happens.  I have tried pasting in \$PRP:"DrawnDate"  or SW-Drawn Date (or SW-Short Date) etc.    But those all give an invalid value error.