Great set of photos Alain. Interesting and weird looking plant. I usually see one in very plant show I attend, but I've never tried to grow a Massonia. Your plant looks super. The sequence is great. I especially liked the emerging bud.
When I got my first I was told to grow them like Conophytums. I think this covers the watering period but probably more repotting is needed. It takes months for the bud to develop under my conditions.