Map Ranks and Firefox 4

Has anyone else had problems running Map Rank GL with Firefox 4? Thanks.
Conquer Club, a free online multiplayer variation of a popular world domination board game.
http://www.tools.conquerclub.com/forum/
http://www.tools.conquerclub.com/forum/viewtopic.php?f=528&t=144870
premio53 wrote:I guess my only other question is where can I download an older version of firefox for Lubuntu?