Hi Dr Nicolas,
I have exactly the same set up as you have but I have now learnt the little foibles! This is my procedure for starting SD with my PF Core.
1. Make sure your iPad is open but the SD App is closed. Also make sure you have the latest firmware and Alps Obstacles database installed in your PF Core. This is available for downloading on the PF Core website for a small fee. PF Core will not work without the mandatory yearly database update.
2. Start the engine and then turn on the avionics (including PF Core & Air Connect). PF Core goes through a boot-up process which lasts for about 2 minutes. When it has finished booting up, it gives a rather loud audible beep in your headset! This is providing that you have your radio/intercom switched on AND you have purchased the optional audio license for your PF Core device.
3. Whilst PF Core is booting-up, go into your iPad Wi-Fi settings and make sure that it isn't connected ort trying to connect to a nearby Wi-Fi such as a WLAN in your hangar or house.
4. Quite soon after the PF Core boot-up beep, you will see your iPad connecting to your Air Connect WLAN. Wait until you see the little Wi-Fi icon appear in the top left hand side of your iPad. Now open up the SD App.
5. When you are ready to aviate, select 'Go Flying' and then select 'Use Flarm'. There should be about a message saying 'Waiting for Data' and then after about 5 seconds the aircraft symbol should appear wherever you are.
I have found that if I accidentally turn off my PF Core (it's on a separate switch in my aircraft) and then turn it on, the connection to SD is lost and you will get a message telling you this. Turning the PF Core back on DOES NOT re-connect it to SD for some reason - even after the boot-up beep is heard. I have to close the SD App, ensure that the Wi-Fi icon is showing and then re-open SD.
Similarly, if I close SD in the air and try to re-connect it to PF Core (which is the same as you shutting your magnetic case), it doesn't want to do this. I have to close the SD App, check I have the Air Connect Wi-Fi connected and re-open SD again.
I don't think there is any problem to solve; it just seems to me that it's the way it is! I have been using PF Core now for about 4 years and I think it's brilliant. Now that SD shows traffic radar (this display only occurs if your PF Core has been triggered by another aircraft with FLARM, ADSB or TXPDR - it doesn't automatically display as soon as you turn it on), it's even better.
I read in the Help Files that if you have a smart 'phone with SD installed, when the traffic radar display is showing on your iPad, you can then go into SD on your 'phone and under Navigation Options select 'Traffic' and your 'phone becomes one big traffic display!
"If you have a smartphone running SkyDemon, the Traffic Radar is not displayed automatically in the corner of the screen, but instead it can be viewed as a full-screen display, which you might like to use as a complement to the normal map view on your main tablet. To bring up the full-screen Traffic instrument on your phone just open the main navigation menu by tapping the blue SkyDemon icon in the top left-hand corner of the screen, then choose ‘Traffic’."
I hope all that helps!!