Is there any event or action configured in the checkbox. Can you try changing the control of the element that is disappearing to pxTextInput and see if this issue goes off. Also do check if there is any server or client side events associated with the click of the checkbox which is causing this.
yes there are 2 actions configured one is refresh row and other is refresh section ...generally when we select check box we should be getting option to modify the details in that row (calling this feature in refresh section action).
yes i have tried changing the control to text input and text(under data display) but still its dis-appearing.