Only certain scripts need to be loaded in Script Manager. I've stated in the first post in XDA that:
- remount needs to be loaded as it should be the last script that is running so that it will survive the kernel doing a remount when booting
- zipalign can be done in Script Manager to hasten boot time.
- sqlite_optimize can be done in Script Manager to hasten boot time

The "How do I know if it works" section only validates some portion of the scripts (not including the remount etc).

You can include it if you include proper credits.

Copy whatever in the /system and add the lines to set permission in updater_script

You'll need to put it in /etc/init.d

Putting it init.d will slow down boot up though as the scripts will need to be done before boot up occurs, which prompted me to use Script Manager instead.