Yes, you can adjust maximum voltage in INDI Control Panel (In App, go to Ekos --> INDI Control Panel --> SM Pro --> Power). By default, it's set to 12.5v so if input voltage is detected above this, it will not allow you to turn on the 12v output. As indicated in the manual, the outputs are indeed unregulated. Therefore, if you adjust this value then adjust it at your own risk. Over voltage can damage some devices.

1. From StellarMate App

2. From INDI Control Panel