But let's face it, a lot of people aren't going to read, no matter what, unless forced.
You could put a big sign in front of them and they would just walk around it. They aren't going to think something might apply to them, until the point they can longer proceed.
Then, as we notice, a lot of them come to the forum and still simply refuse to read anything at all, even making near duplicate thread titles to explain their problem. Apparently it's easier to write than read.
Through discussions, we have definitely made some useful changes in the past few days to avoid difficulties entering the code, but we probably can't go much further. I think it's time to get the full version out there and this episode will become a thing of the past.
But maybe, as I said, I could make that "S3 licensed: User name" button flash in two situations:
1) Unlock code is wrong (zero, just now, or requested a new code at any time)
2) License level is wrong (upgraded on site but not yet unlocked again in game)