It's the restriction of the current implementation of the 'checkbox' formatter. It uses just the standard checkbox which is disabled. It one clicked on any disabled control no click event will be fired.

STOP!

During writing the answer I become an idea how to modify the standard 'checkbox' formatter to make the disabled checkbox do clickable. I implemented the solution with respect of the custom formatter and unformatter. The idea is to place invisible div over the disabled checkbox. In the case if the user click on the disabled checkbox 

The demo shows the my solution.

@Tony: if you read the post, probably one should modify the standard standard 'checkbox' formatter in the way? If you think that one could have compatibility problems with such changes one can introduce new "clickableCheckbox" formatter.

Best regards
Oleg 

Help me please with this problem:

if I made a cell with properties like ->  formatter: 'checkbox'  and  edittype: "checkbox"

Then I try to edit cell and click at the checkbox - I have nothing, but if click on the cell then checkbox is activated and I can edit it.

How can I edit checkbox without clicking on the cell?

Thanks