Hello, I experienced the same. What I did was to install China stable (be sure not to lock) which went fine with wifi on after reboot. Then I installed TWRP recovery again and only wiped to factory reset with install of stable eu rom. Since then it worked for me, wifi is on after reboot. Probably this helps anybody.
Fixed the wifi and the problem of moving folders that was impossible.
I have installed the latest version of xiaomi.eu that has come out: xiaomi.eu_multi_MIPAD4_V10.3.2.0.ODJCNXM_v10-8.1 and everything is perfect.