I'm not following any of the solutions here. sashafiero, what exactly do you mean?
Also, llliW, I went to that thread and it's very old; none of the code references are proper anymore, so I don't know what changes you are referring to.
Still stuck with no solution. The author also seems disinterested in this issue as well as he has ignored the request to review and comment on this thread.
To reiterate, regardless of using CAPTCHA or not, when the submission is processed, after the spindle disappears, nothing happens (e.g. no confirmation it was complete). Note when I have CAPTCHA showing, it changes the values, but that's it.
I would prefer to show a "Thank you!" screen rather than seeing a little "done" response, but right now, I can't even get that...