The Ray Allen trim servos have that ability built-in. Having a manual over-ride to disable and reverse trim is also a good idea. The AP Button panel has a 3 second limit and will disable trim if held for more time but 3 seconds is too long, IMO - at least for my plane.
I thought I read on the VAF forum that Garmin added serial to the servos for backup but not able to find it. The current install manual agrees with you. Only connected to the 507 or 307.
Folks using the TT AP are likely doing so in type certified aircraft for which the Dynon AP is not yet approved. If you can use the Dynon system, do so.
If the ball is off center in straight flight, it means the ARHRS is not aligned with the aircraft. It will need to be slightly rotated to correct this. Compass calibration is done roughly on the ground, then fine tuned in flight by following the instructions.
There is a link on the Seattle web site on how to download. I am not yet using it but will be getting my IFR cert next year after installing an IFD-440.
http://www.seattleavionics.com/ChartData/default.aspx?TargetDevice=Dynon
From the install manual, rev AF.
No GPS
GPS is an essential part of a SkyView system. If you do not have a working GPS, you cannot set
the system time, calibrate the compass, or use the moving map.
You do not "load" the files from Seattle Avionics - only the monthly FAA chart data (DUC files) get loaded. IFR charts must remain on the USB drive for access by the system.
Highly trained does not equal highly capable, which was the case in that accident and many others. To say auto-trim poses some kind of risk with that kind of comparison is apples/oranges.
There is no need for an avionics master with today's avionics. That said, the radio should come on regardless of the order in which you power them up. Stein does great work. Give them a call or email and they'll figure it out.
FF talks to SV via WiFi, not BT. The 430 communicates with the SV via serial and ARINC-429. If you want to send the flight plan to the 430, you'll need a FS 210.