I've successfully installed litespeed and replaced apache on my cpanel server (I should add the difference is quite incredible). I'm just having a problem with re-writes on a couple of sites.
I use some software called Symphony and it relies quite heavily on rewrites, you can see the contents of the htaccess file here
This is caused by a bug in our rewrite engine, will be fixed in 3.0.2.
As a temp fix, you can try replacing "REQUEST_URI" with "CURRENT_URI", which is LiteSpeed specific rewrite variable.
3.0.2 will be available soon.