Have been using check out wizard in some layouts

Just a note
I have noticed that if the checked out field is always required and is not configurable
- when displayed in a form it has a * next to the field
- but if you take a look at the table in the checked out properties box the required option is unchecked

Now back to the topic TASK BUTTON automatic checkin / checkout

May i suggest a checkout task / function button (the same as publish / unpublish)
- available in both the item and collection and item layouts to automatically check in / check out the item using the current date+time and current user

and if we could get the required by default [JS validation] removed from the field it be great as well

just a thought

Required problem is fixed now.

The best is not to instance this field in the form. You can try, but it is creating problems.
If you want to checkin your items, use the Joomla native operation for that : Global checkin.
In the sandbox you cannot access to it, but everytime you regenerate, your items are checked in. So regenerate.

Thanks again
"Global Checkin"
I guess I was just over thinking the problem - some times we overlook the most simple things and re-invent the wheel