I repeat, now the third time: As long as nobody at least wants to give me the img source url to one of the group icons, there's really nothing I can do, since it works fine for me.
The code in the plugin calls for the groupthumb, and this code has not changed for a long time now:
Code:
$statusimg = "image.php?groupid= " . $cel_groups[groupid] . "&dateline=" . $cel_groups[dateline] . "&type=groupthumb";
Is this type-parameter in the URL that calls the group icon on your forumhome?