Not returning success, abort, error, or anything

What can cause a server action to not return a success event (or ANY event)?

I have a form. When it’s submitted it has an “on success” event.
But, it was weird - even though I got the correct JSON response the form wouldn’t return a success.

I’ve tried adding other dynamic server events to the form: done, error, unauthorized, forbidden, abort, invalid, and even the start event.

The ONLY one that returned anything was the start event.

Then, I uploaded the OLD dmxAppConnect.js file to my FTP (the one from before the update on Friday) and the form, and success event, worked just fine.

So, when the dmxAppConnect.js from October 17th is loaded it works fantastically.
But, when the dmxAppConnect.js from October 21st is loaded returns no event.

What could possibly cause this?

(i previously posted a long and less accurate version of this in the bugs area. But, now I realize it’s related to the action not returning any success, or other, event when the newer dmxAppConnect file is loaded)