I would just like to propose the following changes.
Change one
Consider this text
Never change the default PHP Interpreter of your operating system.
If you need other PHP versions, use the ones provided under Configuration -> PHP Interpreter.
This says don't ever change you PHP interpreter but you can change your PHP interpreter here.
I think this reads better
Never manually make any changes to the PHP Interpreters of your operating system with the CLI, this will break KeyHelp.
If you need to change the default PHP version or add additional ones, they can be added and configured here (Configuration -> PHP Interpreter).
Change 2
Consider this text
Never upgrade your operating system version manually.
I think this reads better
Never upgrade your operating system version manually, this will break KeyHelp.