If I recall, and could be wrong… high-idle is a must for flight, because if/when you pull power to idle (like on short approach), and then need to add power… the spool-up time is less. Not sure if that is modeled…
Not a must, but you can keep them in high idle for faster response. but if you’re on profile, you wouldn’t need to anyways. When I flew the 90’s and 99’s they’d always be in low idle. High idle gives you just that, a higher idle output. In flight it literally changes nothing unless you bring the power to idle.
High idle is not required for flight. All low/high idle does is set the min idle speed/RPM for the gas generator. High idle good for - short field since you will get faster spool up selecting reverse, ac on while on the ground (one engine to high idle)… maybe some other cases I am forgetting. That being said, it’s up to the operator. Just know that the condition lever is not a mixture control. It just sets the min idle rpm.
Edit - V1Rotate summed it up and got the response in while I was typing 
My only time as PIC, is light pistons… but I did sit right-seat in C-90… The pilot explained how slow the “throttle response” was, compared to a piston… adding that high-idle, reduced that lag… or that is how I remember it.. 
Since the new wind gust modeling… “staying on profile”, is a handful… I’ve been all over the throttle, on final.. 
I’ve got problems with pressurization. I set the right altitude, for example 18.000ft on the inner circle. The plane doesn’t seem to pressurize itself. What do I need to do more? The needle is on the gauge is also not increasing or decreasing. Do I need to turn another switch?
Bleeds on?
Bleeds open?
You can test it on the ground by setting the pressurization to zero then holding the pressurization dump switch to test… should show a cabin descent.
Obviously I’m doing something wrong here. I started both engines and have both generators on, gen ties normal, inverters off. On the annunciator panel I get: L DC GEN, R DC GEN and BAT TIE OPEN. I don’t get electrical power unless I have EXT POWER on…
Look down on the pedestal.
You need to put both bleed air valves to ON (The top position).
Anyway the pressurization system is a bit buggy. Warn/Caut annunciator lights do not properly reflect current switch position. Cabin altitude and cabin v/s needles won’t react when the bleed valves are at/ or below ENVIR OFF. Some stuff to fix for the SP 
Make sure when you turn the generators on, you reset them. Push them all the way up and they’ll spring load back to on. Also make sure you turn the inverters on.
make sure the inverters are on, and reset the bus sense by flicking the switch up for a second and then letting go
Got it. Now I only have BAT TIE OPEN on the panel.
That was it. A bit strange, as I started on the runway. Thought that the plane was fully configured.
Hey everyone! I am having an issue with the external power annunciation blinking - Is there something I am missing. Engines running, generators reset and on and externally, the power is disconnected (I used the MSFS ground menu to disconnect the external power - is this correct?). I feel like I have missed something.
A quick CTRL+F search through the manual for external power doesn’t reference anything specifically about this.
The EXT PWR annunciator should blink only when there is a GPU connected to the EP slot and the EP switch is OFF. Here it seems like the GPU is always connected to the aircraft while on the ground. Perhaps it is intentional, cannot tell.
Ok. Good to know it’s not me. Once I started to taxi, it extinguished.
Seems like GND PWR is automatically connected from the start, yes.
Anyone else getting this from as soon as the aircraft is loaded? Happens from cold & dark all the way through to fully started. None of the switches change the screen and none of the radios light up.
The fact that it is happening with the batteries off makes me think there’s something wrong with my install or activation.
no no it s normal behaviors, like starting / loading screen when you start a computer