To be perfectly honest I hadn’t looked into it that deeply. The reason why I thought I needed the bus tie switch was because I saw it being switched on when I originally tested the startup by pressing “Autostart engines”. It sounds like I dont really need it anyway. I have both the APU and ground power working but I had nevere actually tried starting up without the Bus Tie on to see what happens.
Many thanks for that, you have saved me a lot of bother. My cockpit is a replica of the Embraer Phenom 300 so it was always a bit of a stop gap using the Longitude for me as I wait for a Phenom to be developed (if that ever happens).
Best regards
Stinger