Hello,
Our Templates will install without any issues provided that you are following the correct procedures and have the proper server requirements.
http://www.shape5.com/joomla_tutorials.htmlhttp://www.joomla.org/technical-requirements.htmlAny Extensions will also work with our products as long as they are supported by the CMS and use proper javascript calls that do not conflict with other site wide functions. If you need help setting up a particular Template please post in the correct forum and we can assist you from there.
-Mike