Hi Jason, I would prefer to use the positioning and floating of the HTML object so you can position the error message below the custom label.
More of a workaround than a solution, but you could place another invisible attribute under the text on which you would anchor the feedback. The user would not tell the difference.
The solution I used was to position the text above the checkbox and add "pull-left" to the checkbox and decrease the padding. Its a messy workaround for something that I think qould occure quite often with checkboxes?