I'd like a way to track how many times a response has been editted by a participant.

I thought this would work, where I have an Equation type question, and the equation would be:

{Count = Count +1}

But after my first submission, the value saved was 12 (funky math there!).

Can you suggest an approach to let me track number of edits?

Depending on the position of the equation question and the structure of the survey the value can be anything I don't see a solution inside LimeSurvey.
It would be great, if token attributes or a global variable storage could be modified via EM userwise. I don't see this at the moment.