Hello everyone, I thought I will share this here so more people can find it.
A while ago I made a free tool that allows to download raw data and reports CSVs from Piwik PRO without struggling with the authentication, any type of scripts etc. It has a form of Chrome Extension.
Basically it provides a in-browser GUI for handling your query definitions and displaying progress of the download, and saves files automatically.
You can check the video to get a feel of it: https://www.youtube.com/watch?v=7r-_JD8WuWY
Link to the website with presentation and download link from Chrome Store is here:
Maybe someone tackling similar issues with downloading raw data as I did, will find it through this post and save some work by using it.
Also, I will happily welcome any suggestions/feedback/bug reports 
I hope such a post is within constraints of the community forum, I chose “lobby” category as it is described for “sharing your content” 
Cheers!