Thanks for the feedback. We'll post a reply to each of your points below:
The flaps in the PA28s are purely mechanical, so there is nothing to prevent them from moving in a cold and dark state.
The autopilot behaviour is largely dictated by the GPS unit fitted. With the "GPS 100" fitted, there are no external GPS units fitted, and the autopilot behaves as per our code. With an external GPS unit fitted (WT GNS 430/530, PMS50 GTN750, TDS GTNXi), these GPSs feature their own custom autopilot code, so slightly different autopilot behaviour is expected.
Thanks for the feedback. We'll log this on our internal feature request tracker as something to consider for a future update.
Yes, the KX170B is set up to reflect the real-world configuration where it doesn't support 8.33 kHz spacing. We do have a feature request logged for this to see if we can add support for it within the current model, but we aren't able to guarantee if anything will be possible with that. In the meantime, 8.33 kHz spacing is supported on the other GPS units.
Mark - Just Flight