To reproduce:
- Set the theme to FluentDark and the set RightToLeft = Yes.

Workaround:
radToggleSwitch1.RightToLeft = RightToLeft.Yes;
radToggleSwitch1.ToggleSwitchElement.Thumb.MinSize = new Size(13, 13);
radToggleSwitch1.ToggleSwitchElement.Thumb.Margin = new Padding(2);