When opening your workflow and attempting to edit the start event you may experience the following:
500 Internal Server Error: Inconsistency detected between SmartObject 'YOUR SMARTOBJECT NAME' and Service Object 'YOUR SERVICE INSTANCE NAME' during loading of the SmartObject Definition Property: 'YOUR PROPERTY NAME' not found in the Service Object 'YOUR SERVICE INSTANCE NAME' definition.
You may experience this issue if you refreshed the service instance after making changes to your data source and then changed the name of the properties manually in the SmartObject. This puts the SmartObject used in the workflow in an unusable state.
The correct way would be to republish the existing SmartObject to update the property changes.