Lem 5 Pro Compatible Firmware

Hello,

I have been trying to flash firmware to my Lem 5 Pro but without any success. Using the 5.17 I downloaded official firmware from this forum for smartwatches other than Lem 5 Pro. Mostly I would flash successfully but the device wouldn’t boot, with notable exception of x5 which got stuck on boot.

The ones I tried:

x5
x6 air
Thor
Les 1
Lem 6
I4 air, I6 and some others but all in all mt6580 family

So the result would be either won’t boot or bricked and i both cases i would get my Lem 5 back with w618_wgl.lemfo_16g128g.common.80.emmc.w.s.170911 without any problems. I tried all the methods I could think of in Sp Tool: dl, firmware upgrade, with preloader, without preloader even format all + dl (I know i shouldn’t have done but I am not going to make calls from this device). I tried with rooted device (with an app) without root, same result.

So, am I doing something wrong here or it is just not that compatible? Also does it have to be mt6580 firmware or can it be done with firmware for other chipset?