We have a more updated and thorough article on this at the Developer's Blog:
Yes i do.
I have tried to use http://app-lon02.marketo.com/index.php/leadCapture/save2 .. but im just getting an Error 400 all the time and "Form error, no subscription ID" error.
so just a normal <input> from an external form.
Do you know what the "subscription ID" in a form is? i cant find any documentation on it
My example is not posting to leadCapture/save2. Are you sure you've tried it using the exact setup I showed above?
Are you also adding the Email address field so Marketo knows what lead you are trying to update? Otherwise it doesn't make any sense...