re: How do I get dynamic Choice field to work?

If you use regular choice fields then you have to manually edit (by editing the field) the list any time you want to change it.

If you use dynamic choice fields then you only need to create a new record in the table that the field references.

The regular choice field is good if you don't want end users modifying the list or if the list doesn't change dramatically or is not used in many different tables. The dynamic is good if you want end users the ability to modify the list or you have a constantly changing list or is used in many different tables.