On kendo.web.js v2013.2.725
line 43592 the workaround is in place on the select method:
node = $(node, element).closest(NODE);
that fixes when you click on the icon for example or the checkbox of the node and allows a fake non buggy behavior.
as soon as you get something deep inside you are bad. the line above will find the inner widget and game over.
Can you change below from e.target to e.currentTarget like in the _mousedown function???????
As soon as you do that I will download the new private build on customer area.
I've checked and build v2013.2.801 is bad as well.
node = $(e.target),
//this should be e.currentTarget
see it fixed in the new jsfiddle:
It took me a lot of hours to fix that so find attached for someone that needs that in the meantime while it is not fixed.