Unable to install in to Joomla 2.5

mega_restaurant_quickstart_demo_installation_package_j25

Will not install as a package, it looks like it will accept the file, then after 30 plus seconds the screen refreshes with no message, If I check out the templates in Joomla it is not listed, however if I try to install the basic empty version it installs fine?

Please help I need this sorted quickly.

Regards

Andrew

mega_restaurant_quickstart_demo_installation_package_j25

Do not install this package from back-end.
This is full demos package, and you install it same as install a new Joomla!

Thanks