@ Andrea
re: This is the site in which I am receiving the error.
Checking my access logs it seems you are trying to activate on http://www.mhaatwork.org/mhaatwork which is different from http://mhaatwork.org/ thus the activation limit error.
I’ve manually deactivated the http://mhaatwork.org/ site so you should now be able to activate on the http://www.mhaatwork.org/mhaatwork site.
re: The template is still working.
Correct. The extensions and templates will continue to function. I personally believe it would be pretty hostile to prevent something from working if the license was invalid or expired. What will not work though is in admin updates since the license can not be activated so it would not validate when trying to do updates.
Hope that answers your question thoroughly!