ISPConfig 3 is not a daemon, so it does not has to be started at all as it works as cronjob. The start script you refer to above is for a different software "ISPConfig 2", nothing thatyou read abut ispconfig 2 applies to ispconfig 3 except of the first part of the name.
If you have a probem that ispconfig 3 is not applying changes to disk, take a look at the debug instructions.
http://www.howtoforge.com/forums/showthread.php?t=58408