Help me to Flash radio :(

[Shavkat]

Hi!
I had bad connections with new 3.27 radio, so i flashed stuck 2.27 rom.
But i having same problem after flashing.
So i need to flash Radio 2.17.
I downloaded Radio 2.17, but i can't flash it.( stuck in 0% )
My question is:
-To able to flash, do i need unlocker? Or i can flash 2.27 Radio without unlocked PPC?
-What Radio version is better? ( at the moment i have Radio 1.47.01 )
And wow i noticed with now, i have GPS icon near to clock (black triangle) STRANGE