On most of the form component there aren't options to change the styling but in the version of MyDesigner I'm using latest.
The combo box, drop box, multiline text all have styling options in the settings. Settings that don't work or work as predicted I would consider a bug if I wanted styling options for the switch or check box or have texture options for surfaces which i do that would be a feature. Having what already is there not work is a bug in my opinion.