Achievements fixes on Windows

We had some reports of Achievements being flaky on when they granted on Windows. We traced this down to it being when the person is playing pass-n-play, the achievements were being calculated from the perspective of the last character that played (that's why they were granting about 1/2 of the time).

We've just deployed the fix tonight. Next change will also be more bugfixes.

Thanks for playing & for reporting issues in the forums!