Cannot get Manual to Work

I have used all the other settings and am very happy with this plugin however, I cannot get the manual option to work.

I have set the ad block to manual and inserted this code in my page:

{adinserter Websites and Blogs Posts Manual}

However, the ad block does not appear. I have tried capitalizing the text, adding underscore both on the ad block and in the post and all other kids of combinations, but nothing works.

Please help – thanks!

-Matt

http://wordpress.org/extend/plugins/ad-inserter/