Problems after migration Joomla to 3.1

I have just make a migration from Joomla 1.5.26 to 3.1 with a SPupgrade. Everything is working correctly. And the end I have uploaded the 2.5 version of MyStore. In the backend everything seems to be OK. But on the frontend I don't see anything. In the sourcecode you only see a "1". Is this a PHP-problem of the installation of a problem of the template? When I switch to Protostar (default-template of Joomla 3.1) the site working correctly. Or is the template not ready for 3.1?

Yes this template does not support joomla 3.x versions I am afraid.