They can be used for temp sensors and I was looking into giving you instructions however I realized the "Accessory" option when you click on a DB9 port is only setup for V1 controller so the pinout is wrong for V2 and V3. Using that option the pinouts will be wrong for your controller and won't work. Sadly I did something that messed up the layout for the "Advanced" view which would have got you going. I'm working on fixing both problems, the only thing you can do for now is leave "Accessory" option as a Power Bar and then set 6 or the ports as dosing pumps which should work however you won't be able to use the sensor ports on extension.
This is complex so will take a little time to fix, hopefully I can have it ready for tomorrow or the next day and will post some updated files so you can patch it. This could be related to why you can't add dosing schedules. Once you set "Accessory" option for DB9 back to Power Bar it might work.