If you LiteSpeed PHP setup give 503 errors, you may have PHP configuration problem, usually it is because the version of a loadable module does not match the PHP version used. You need to recompile the loadable module to fix it.
Some trouble shooting techniques:
check lsws/logs/stderr.log and lsws/logs/error.log.
try to start the lsphp binary with matching user id with command like
sudo -u nobody ./lsphp5 -i
compare the phpinfo() page to a working installation, sometimes, due to permission problem, php configuration files cannot be fully loaded.
strace/truss/ktrace a lsphp process, it shows all the system calls made by the process.
Is this what you are talking about?
How would it be a different version if I used the web interface to compile?