With form decorator the checkboxes jump a bit to the left when cell is opened: https://www.screencast.com/t/5HwXW6kgVhb

Without form decorator they get centered because of the 100% width they get https://www.screencast.com/t/oxc75Bu6lM

It comes from the combination of two things:
- by default, the grid cells have a left padding (as well as padding to the other sides, but that's irrelevant now)
- the batch editing container does not have left padding so the editable element can better align with the text in the general case (textboxes and other editable elements usually have some left padding). With a checkbox there is no textual input, though, and so it appears to shift to the left because the left-padding of the cell is removed by the batch editing.

Workaround:

		<style>
			/* note: the margins may vary in different skins, inspect the rendering if there is a  */

			/* for form decorator */
			html .RadGrid td.rgBatchCurrent .rfdCheckboxUnchecked,
			html .RadGrid td.rgBatchCurrent .rfdCheckboxChecked,
			html .RadGrid td.rgBatchCurrent .RadCheckBoxList {
				margin-left: 12px;
			}

			/* if no form decorator */
			html .RadGrid td.rgBatchCurrent input[type='checkbox'] {
				width: auto;
				margin-left: 16px;
			}


			/* in case you have radio buttons even though they are not a supported editable control with batch editing*/
			/* for form decorator */
			html .RadGrid td.rgBatchCurrent .rfdRadioUnchecked,
			html .RadGrid td.rgBatchCurrent .rfdRadioChecked,
			html .RadGrid td.rgBatchCurrent .RadRadioButtonList{
				margin-left: 12px;
			}

			/* if no form decorator */
			html .RadGrid td.rgBatchCurrent input[type='radio'] {
				width: auto;
				margin-left: 16px;
			}
		</style>