Add Event bubbling...

[dkimbell13]

Your events do not bubble up!
document.querySelector(this.wz_class).dispatchEvent(new CustomEvent("wz.update", { detail: { "target": this.wz_class, "elem": document.querySelector(this.wz_class) } }));

could/should be something like...
document.querySelector(this.wz_class).dispatchEvent(new CustomEvent("wz.update", { bubbles: true, //Enable bubbling detail: { "target": this.wz_class, "elem": document.querySelector(this.wz_class) } }));

This is prevalent throughout your event dispatching. Please ensure that events bubble, so we don't have to add event handlers directly to the .wizard class element, and instead can bind to the document, with a reference to the .wizard, in the cases where we are dynamically adding a form wizard to our web page.

Thanks!