I created a new option, and defined it as an On/Off checkbox. I gave it a value of false.
Bug 1: When returning to the AdminCP, the checkbox is checked. Expected behaviour: Unchecked. (Does it perhaps need to be set to "false"?)
Bug 2: I then edited the option, and tried setting it to a Text Box instead. I removed the default value, but when saving, the default value is retained. The only option is to remove the option and recreate it.
Bonus points: Please explain what the possibilities for the fields "Format Parameters", and "Array Sub-Options" are? Also, just for some additional clarification, what would/could the callback here be used for?