You probably can install CWP on the CentOS 7, but we didn't run any tests on it, so you will have some issues for sure.
Do you plan to support CentOS 7 ?
Yes, we do plan to support CentOS 7, but with the newer releases.
When do you plan to support CentOS 7 ?
CentOS 7 has still a lot of missing dependencies so it is not possible to have the full functionality of the web hosting server with it.
The exact date or release version is unknown, but we will probably try add it before the end of 2016 if possible.
We are still continuously developing control panel for centos 6 so its highly recommended to use centos 6.
After we complete the centos 7 version of cwp, we will still support centos 6 and provide the full updates for it.