GoogleFormAnalysis, is a typical project that was made because it was not available ;-). I just haven't found any tools for analyzing Google Forms. Although you can view final charts, there is no way to filter, nor to group data. GFA gives you this missing functionalities.
The description of the tool is in English so I'm just going to say that you have to know how to write in JavaScript to use the tool. For now I had no need to do a one-click tool to generate all files, but maybe some day... if there will be demand for it.
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