When attempting to modify\create a custom script on a particular table column within Designer | Database Schema, the template field (from the "Quest" and "Custom" tabs) can be used to calculate properties automatically.
Generally, a template runs if other properties were changed, and it in turn calculates a new value depending upon those properties (e.g. the CentralAccount from the FirstName and the LastName values).
A template will be executed every time a value is changed which is referenced by a $-notation in the template.
For example, the template for the UserPassword@ADSAccount column has the following $-references:
That means this template will run if one of these fields was changed.