I'm having issues configuring an External Data Column with Nintex Forms 2013.
I've already created my External Content Type and if I create an external list based on it, I can see the correct values.
In my form I've put an External Data Column, not connected to any list column, and I've tied it to that External Content Type, I've changed the display format as Dropdown list and I've selected one of the columns (text type) returned by that content type as field to display. (Have a look on the configurationin the image).
If I look at the published form, the dropdown field list is empty, do you have any suggestion on how to solve this?