KW_Radio has no documentation

[mobius3]

New widget, KW_Radio, has no documentation. @Emersont1, since it was you who added it, maybe it is better if you create it? :)

[Emersont1]

Yeah, sure I'm currently trying to work on getting a 2D radio button which is proving trickier than i first anticipated, but as soon as i've got that sorted, i'll PR in the documentation