RATINGS - the rules

I'm not obsessed about my rating - honest! - but I would like to know
just how this system works.
Just for example: an opponent invited me to claim a win by timeout
because he was playing too much chess and wanted to abandon the
game. It was a rated game. Only nine moves had been played and it
was a roughly level position. My rating did not go up.
What is the minimum length of a rateable game?

Please can you tell me the id of the game in question and I will see if
can explain what happened. Your rating should have gone up -
unless your opponent's rating was very much lower than yours.

-Chris

Game id: 16150. Opponent's grade: 1422 (I think) at start of game;
1245 at end. My grade: probably low/mid 1300s at start; 1379 at
end. - Gordon

Chris - Very similar case. I just claimed a win by timeout (in a
completely won position). Opponent's grade: 1236 I think, at the
time of the claim; now 1222. This time my grade went up from 1379
to 1389. So why didn't it go up before? - Gordon