My name is not an alias and doesn't need quotation marks.
The APU works for me on the Metro and that's why I've added it in the first place. I also seem to remember it working in SP2, but I could be wrong since I've upgraded to Acceleration/Steam years ago.
So therefor, SP2 simply might not support the APU on anything else but jets. Could be that ACES implemented the functionality for the EH-101.
On the Metro, your only option is to use the battery and get the engines running as quick as possible (the next Metro upgrade will feature more realistic batteries).
For the Osprey, I am not sure what can be done. If bleed air is the reason the APU is required, Maryadi would need to implement an optional "no bleed" mode to start the engine with. For infinite battery, there's the
Code:
electric_always_available=1
line for the [electrical] section in the Aircraft.cfg or the "Infinite Battery" setting for FSUIPC as a workaround.