@advocatux

Hope this is the right one:
https://spflashtool.com/

So i found these posts:

https://askubuntu.com/questions/644245/ubuntu-mx4-not-detected-on-ubuntu-sdk?noredirect=1&lq=1

https://forum.xda-developers.com/general/help/meizu-mx4-ubuntu-to-android-flyme-t3172828

and it seems MX4 has definitely some problems with usb connection, it appears it's a common issue, but someone found that "adding the vendor ID to adb_usb.ini seems to help".

Of course there was no such file in my pc fuuuu..... so continued looking and searching and found this:

https://stackoverflow.com/questions/9709263/google-android-usb-driver-and-adb

which basically says you have to modify another file: android_winusb.inf with other data. (all the instructions in the link), i did, no luck. I then re-installed the usb driver and made sure it was fine, and finally.. adb seeing my device! What a battle it was.

And for today that's enough. Tomorrow I will try the adb method and pray to God it will work.
Sandro