How to install livezilla or other chat inside Magento?

I have installed Magento on CWP on centos 7, but I can not install it in any way (public_html / magento / livezilla) livezilla I'm having the error below

Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator at webmaster@pluscenter.com.br to inform them of the time this error occurred, and the actions you performed just before this error.

I turned the internet behind the solution, and it apparently does not exist.

More information about this error may be available in the server error log.

Thank you for your attention and support!

try http://forum.centos-webpanel.com/centos-6-problems/upgrade-to-cwp6pro-then-error-on-wordpress/msg15849/#msg15849

Thank you, it worked perfectly and first