Keeping your batteries calibrated as DJI recommends is SUPER important. This is what allows the battery to know its state. If you don't do the calibration process on a regular basis this is exactly what happens.
1. Map Pilot will honor the battery warning settings you make in DJI Go.
2. You can see some battery information in the debug panel. The debug panel is accessed by tapping and holding the top status bar for 8 seconds until the panel shows. Same to hide it.
3. We are looking at ways to handle this. On smaller devices it is hard because of limited real estate but we will likely come up with something for the iPad in the near future.