did you download the entire GitHub repo (download button on GitHub) or just the extension (sense-export_latest.zip as Aiham states). You should download just sense-export_latest.zip and then install the extension. Just tested, works without any problems.
Is there a good way to export a qliksense table with formatting and colors to excel. I have been looking for this for a long time, but this do's not seem to work. Is there maybe a extension or is it scheduled for the next QS release any update will help.