Answer
Check the ViewName property set in the screen's .Designer.cs file — it needs to be in ALL CAPS exactly matching the actual view name (for example this.NamedProperties.Put("ViewName", "USER_ALLOWED_SITE");), not mixed case ("User_Allowed_Site"). If it's set in mixed case, custom fields silently fail to bind to the screen even though publishing succeeded and the field appears correctly in the CFV — correcting the ViewName value to all-caps resolves both the missing Reload Configuration effect and the custom field not displaying.