Well, I need to do this for my sim league. And it should help fellow sim league commishioners that sim with nba live.
1. Load the season
2. Exit back to the Nba Live Screen (make sure u have EA's Patch)
3. Start a new dynasty
4. Sim up to the game that you left off on in your season (If you mess up, teams will play more than 82 games).
5. Save and exit the game.
6. Open the folder "My Documents/NBA Live 2005/Saves/(Name of the Season)
7. Copy all of the files in the folder, with the exception of the 3 .dat files (settings.dat, saves.dat, season.dat)
8. Go to the folder "My Documents/NBA Live 2005/Saves/(Name of the Dynasty)
9. Paste the files into the Dynasty folder
10. Load the game and enjoy!
It should work! It did for me!
BTW, this also works for multiplayer dynasties!