Ah. Now I kinda see. If it helps, I commish a fantasy hockey league and the league started on 10/6 and I was unable to change the league settings after11/28. If I understand you correctly, you want to limit/charge for transactions. If so, then I would try 2 things based on what you want to do:
1. Lock all moves for the whole season and have managers e-mail you or post messages on the board for all moves that they want. You need to be on the ball with this.
2. I tried this in my hockey league and so far, so good. Don't limit transactions that can actually be made. Just set an amount (0 if you want) and any transaction amount over that amount on the Team & Manager List page costs you X dollars each. The computer never lies.