If you plan to use LiteSpeed with cPanel, you can try install it yourself with the WHM plugin.
http://www.litespeedtech.com/support/forum/showthread.php?t=2160
LiteSpeed Web Server 3.3.15 has been released
This release is mainly to address a few minor bugs and added a cPanel/WHM plugin for easier management of LSWS through WHM.
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No need to use those configuration. try rewrite rule
RewriteRule (.*\.rhtml)$ /cgi-bin/eruby/$1
This should pass the rhtml file as PATH_TRANSLATED to eruby CGI. give it a try.
Were you accessing the vhost by IP or by domain.
There might be a problem with vhost with dedicate IP, fix is in 3.3.15.
You can download it by changing the version number in the download link.
Have no idea, it should be a PHP internal feature.
However, you should find PHP error messages in /opt/lsws/logs/error.log or where ever the log file has been written to.
Please check error.log and stderr.log for errors, make sure the MIME setting is correct for .png, try to load it with firebug extension from firefox.
You should remove the "example" vhost from the vhosts configuration tab.
We have developed a cPanel/WHM plugin for LiteSpeed Web Server Enterprise, announcement is at
http://www.litespeedtech.com/support/forum/showthread.php?p=10990
Please give it a try and post your feed backs under this thread.