1. Done. This has been a feature since the earliest releases of Map Pilot.
2. These do not disappear unless the app is deleted. You have to hit the button to save the map so the offline version of the tiles are saved otherwise it is as you say, liable to dissappear.
3. It certainly shouldn't be crashing if you are offline but where are you sending it? AirDrop works fine if you are within WiFi range of your laptop. The new version that is coming out this week will be able to open the KML files with any app on the device that can view those files (Google Earth).