Please remember that it is still in Beta stage, and that the final release is still months away. The use of any beta software is on your own risk, and you shouldn't be surprised if programs like this will not function at all, or not function properly.
MSN Messenger 7 is not officially supported since it is still Beta.
For more info regarding MSN Messenger 7:
http://shoutbox.menthix.net/showthread.php?tid=32404
/ 
