Possible/ Common Problems.
a) There is a case sensitive bug when auto-detecting the appropriate keys - this is fixed in PR21.
b) IF auto-dict-validation for the form is OFF, or auto-dict-validation for the field is OFF then the "use description instead of code" will not work. So if you do turn auto-dict validation off, set it to ON for lookup fields.
c) If you want to use "Display Description instead of Value" then the dictionary MUST have a key on the Description field. Ie the Table being looked up, must have at least 2 keys, one on the Value and one on the description.