Hi.
When I use K2 2.4.1 everything is fine but if install version 2.5.1 or above "New" button to create new item doesn't work. The same problem is with "New" button to crate "extra field". If I uninstall 2.5.1 version or above and install 2.4.1 everything is fine.
I'm using joomla 1.5.25.
If you want to I can provide you access to my website backend.

Thank you.