Is it possible to make changes to rosters after games start?
The roster adjustments do show in the league activity board once the game begins. I was having problems with "my page" so I went to change my running back right at game time. When I made the change it showed up on the board, which I then switched back to ensure I wasn't taking advantage of the commissioner powers.
I have used this tool to adjust other teams roster that were going to let a bye week player go through. These transactions occured prior to the start of each game and showed no activity on the activity board.