Won't work with Joomla! 3

Hey. I purchased the template yesterday and installed it on Joomla! 3. When i make it the default theme and try to open the site it gives me errors like: Fatal error: Class 'JParameter' not found in .../docs/templates/gk_appsprotech/lib/menu/GKMenu.php on line 104. There also was a problem with undefined DS constant, but I fixed it by declaring it.

So, did anyone encounter this problem? How can I fix it? Tried to reinstall it, didn't help.

Are you sure that you have downloaded the version for J!3.0 not the 2.5 ? Could you try to run the quickstart package ?