I can see 15 products published (yoga mats)
Specifically, I can see 3 "Yoga mat Balance 3mm)
Looking in Litium Studio, Demo assortment, Tools, Traingin Gear, Yoga Mats
I can see 19 products, as far I see all published.
As for example, 710174391 (green) is part of the List of products.
So Questions around this:
I do not get the logic here. Why is not the green 710174391 visible on front end store site (and same question goes for several other variants)
It is possible to define per template how variants should be grouped in listings.
Very similar to group by in SQL, if Color is defined in your template to group by then all items with the same color will be represented by the first item of that color only.