Please contact your host provider ssh as root to server and run.

For cpanel
pear install -f /var/cpanel/rvglobalsoft/rvsitebuilder/scripts/RVSeagullMod-1.0.1.tgz
perl /usr/local/cpanel/whostmgr/docroot/cgi/rvsitebuilderinstaller/autoinstaller.cgi

For directadmin
pear install -f /usr/local/rvglobalsoft/rvsitebuilder/scripts/RVSeagullMod-1.0.1.tgz
perl /usr/local/rvglobalsoft/rvsitebuilderinstaller/autoinstaller.cgi

Fatal error: Uncaught Error: Class 'SGL_FrontController' not found in /home/share/public_html/rvsStaticWeb.php:38 Stack trace: #0 /home/share/public_html/Art-for-Alzheimer's-Awareness.php(3): include() #1 {main} thrown in /home/share/public_html/rvsStaticWeb.php on line 38