(Deckstamp is so good!)
I think any text mode for the field widget should fine, and it could be one of a couple of things. For now, I've made a little working example of .show and sleep[] working together, and one possible autoplay script.
https://crowmorbid.itch.io/little-examples (password: decker)
It's entirely possible that I've written things in a confusing way, but the scripts work and you can look at them in widget mode. I've tried to #comment# inside the autoplay script where it might be a little confusing. Hopefully this helps!