Hi Andy,
The channel through the CMMs is, of course the preferred way to share missions, but until your problem is sorted you can use the Missions board so long as you follow the guidelines for topic titles, etc.
Another alternative is the former Creators Forum hosted by Terry Russell. See this petulant post by Tore:
http://80.95.161.114/shipsim/forum/index.php/topic,25608.msg339751.html#msg339751 (http://80.95.161.114/shipsim/forum/index.php/topic,25608.msg339751.html#msg339751)
We want to avoid a plethora of independent forums if possible, and we don’t promise support for any missions but those on the in-game download list.
Regards,
Marty