Not sure how many of you use this control as I cannot find many posts about it, but in 1.4 the changelog states that this control was enhanced to include 2 new ways of rendering it. However, this enhancement seems to have broken the way that this control used to work. I have a form with 4 of these on it and they are all set to not required in the column settings. This has always worked fine in the past, but with the 1.4 update, all External Data controls left empty throw validation errors("Please select a valid value"). I even tried adding a check box which hides and disables the control on the form so the users can specify if they want to enter a value into it with the check box. Even with the control disabled and hidden, I still get a validation error for any/all left blank.
Let me know if anyone has experienced this or can replicate it as well.