I have the MFL submit lineup widget embedded in another web site, it works great until you submit the lineup, then it gives a Missing League ID page.
The code has the league number:
<script type="text/javascript" src="http://www72.myfanta...E=SUBMIT_LINEUP"></script>
and inspecting the page shows it stored:
<input type="hidden" name="LEAGUE_ID" value="33521">