You sure you're playing the latest version of the game? And yes, the 6th photo is Sasha. I think you're playing 0.5 if you don't know whether that's Sasha or not
No, 0.6.2 is only bugfixes. After that event in the eatery with Sasha's HJ under the table, just come to your room in the evening and talk to Historia again. You'll go to the steam room.
