The unMBA Institute has just released an introductory two-hour course on the Group Works Deck and is offering free access until 20 december 2019 (not sure if including or excluding the 20th). To access the course for free until that date, use the coupon code GWINTRO on the payment page. Thanks to Russell Giesbrecht for sharing his knowledge.
https://unmba.institute/p/the-group-works-deck
I saw that he also has a course on “Graphic Planning and Visual Meetings” with the encouraging subtitle “For the artistically challenged” 
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