To use a custom control in Smart.Form your controlType should be set to ‘template’ and you have to provide a template property
which is the HTML of the custom control type.
Please see this example: https://codepen.io/svetoslavb04/pen/KKByXBB

I hope it helps you resolve your problem, if not, do not hesitate to contact us!

Best Regards,
Svetoslav Borislavov

Smart UI Team