Download the Sync 3.2 files from the Russian forum linked above multiple times.
I assure you 3.4 is not slower than 3.2 though, did you factory reset?
You only need to fix your seat icons with ForScan
some stuff seems different
get a usb with a LED and see what happens, dont do the first USB just try the second USB, black screen is almost always from my experience been due to wrong firmware flashed via forscan/ucds but i guess not the case here.
I am also not a russian speaker but you can figure it out by browsing the files.