Mateusz:
I compiled the Next, I will poke arround and take a look at this.
Thanks
Obviously I assumed you are talking about autonomous flight modes which require all sensors functional and position hold working perfectly. Feature autoland for fast moving racer which usually relies only on gyro (sometimes also accel) is in most cases impossible (you need to stop vehicle usually moving/racing at very high velocity and hold position accurate enough and it would probably crash multiple times before slowing down).
To enable optional battery module you will have to go to configuration UAVBrowser (screenshot 1). This is explained on Wiki how to add voltage¤t sensor by the way (for more details) and also how to calibrate voltage sensing accurately. If you want to calculate coefficients on your own as I tried, be aware that current sensor is reasonably accurate when pulling more amps (motors spinning) when it's low < 1A current flow, it might not match exactly your multi-meter if you would put it between battery. Maybe use default values from table and see if that works for you
It does with AttoPilot sensor.
Enabling battery module will enable (disable earlier and greyed out options) for setting flight mode on battery voltage drop (screenshot 2).
Hope that helps