Most likely you removed an input in the template which is needed to use the feedback form.
The content/action module expects a POST parameter named "ActionCollectInformation" (usually the submit btn) to know that it has to run the collectinformation module.
Make sure you have all the attributes in your template. When you set an attribute as collector but you don't include it in the form, the form won't be submitted nor throw an error.
Edit: Thought I had an issue on 4.1 for a while, but the developer that made the form had removed a attribute from the html based on certain conditions, and the info collector silently failed when the attribute was missing from the request (so solved by hiding it with css instead).