You're probably not going to get them to work yet in the Modern Designer, but you can continue to use the Classic Designer for your existing forms and any new forms that you create that need the functionality.

The Modern Designer has Javascript, but it's very different than in the Classic Designer and doesn't have the ability to directly manipulate the form contents the way that the Classic Designer can.

We use Wacom signature pads in our environment, and any form that needs a signature with them, I continue to use the Classic Designer.  I'm on the final release of Forms 11 (Forms 11 Update 5, Version 11.0.2311.50556) but even with Forms 12, I don't think it will be possible yet to use signature pads on the Modern designer.

The Classic Designer isn't going away, it just isn't being actively developed like the Modern Designer is - it will continue to have its uses for a while and you can even have both types of forms within the same process as needs dictate.

I have adjusted my initial questions to reflect the version of designer. Thank you Matt, I really appreciate your help.