Guys, I have another experience / solution!
I didn't know why, sometimet it gives me the FCC -> CE changing window, sometimes it doesn't. Today I realised how to do it...
I used the versions, I mention in the first post of this topic. I was outgoor, the bird had full GPS signal, my tablet was not under fake positioning, so everything was like it has to be. DJI tells you to switch on in tis order: 1. Remote 2. Bird 3. Tablet, that's wifi, and launch DJI Go... In this order, at the end I alwas get the wlan settings window, and need to switch off the remote before it suck... If you switch on your stuff in different order, it will work... First I switched on my drone, and I launched the DJI GO on the tablet, having no wifi, or any connection. After that I switched on the remote, and it connected everything together, and had no wifi changing warning at all. I was able to use it in FCC, with no fake GPS, and even not higind the drom from real gps signal... I'll post it to the original, topic opener post too. Please, who followed the SW downgrade I wrote, etc, try it, and will see if it works for you too... I hope it does. I'm even curious, if it works with the new firmware (after faking the GPS signal, if you switch on everything in this order, it may not ask you to switch your wifi to CE), or using the new app version...