You could always set up 5 challenge games against your second pilot and then exit one or the other off the map promptly so that you can finish the 5 games you need to sign up for the league.
I tried to join pass-worded league 1527 (Troll Clones), usual password, and got this message:
"You are not an 'Active' Player!
In order to play a league game you must have finished at least 5 games in the last 30 days."
Clones have been at a bit of a lull following our last two leagues, one of which was smaller and I was unable to join, so I haven't even been in 5 games at once in the last 30 days, though I would certainly consider myself to be an "active" player, I log in at least 4 times a week, usually more. Neither of my pilots, Music or Deathglider, meets this requirement (or combined for that matter). For pass-worded leagues, this seems to be a silly requirement. Maybe last 90 days or base it on number of log-ins? Plus a single game at 25 or more turns can exceed a month easily. Can we get this feature turned off or changed for pass-worded Leagues? Please?

~ D:G Music ~
To Contact me best email is: guycoma@yahoo.com