Hello,
Runway extension lines can be always shown up by clicking on the blue Airport icon. In the map, all the actions are by clicking on the markers, there are markers for VOR, Airports, runways, NDB, etc.
Little Map flight plans show show the lines too when a flight plan is loaded, if the airports are marked in the flight plan with an airport waypoint code. You can send me the flight plan that fails and I can check and let you know why.
About the twins: I will think about this for next update, it is not a bad idea but the problem is also room in the screen. When I add extra controls and indicators, users also complaint about there is too much information.
There is no way to make everyone happy but I will do my best to find a way to display twin information.
Thanks!