Property issues

Hi everyone,

   I'm having issues selecting properties in both parts and assemblies.  When I go to File --> Properties and select the Custom tab I get the window with the properties of my template that i'm using, but I can't add anymore by using the drop down menu.  I can still type in the box, but the pull downs are gone... Any idea how to fix this?

  Thanks,

     Rich

SolidworksParts And Features