Hi guys, sorry I have not replied to this thread. WordPress, for some reason, do not notify the plugin author of comments against their plugins. Or if there is a box I need to check the someone please tell me.
I am about to check in a new version of the plugin with the simple change of replacing wp_mail with mail for the actual send. After some local testing I can see that the WordPress function is manipulating the headers and content when it shouldn't be. The new version works fine.
If anyone has any questions please feel free to contact me via my site or post on here and I shall try to work out how to get it to notify me.