i have 4 mastered words and 9 mastered kanjia. This doesn't move, despite the fact that on average I get one word and one kanji reaching mastery 9 every day. For example yesterday (there were a couple today too: What gives? Do words have to be level 9 for all vectors, including those not currently studied?
On your stat page, when you click on the cog in the upper right you get to the page to adjust your stat panel. There you can click on futher cogs for Vocab and Kanji and here you can define what study vectors should (EDIT:) not be considered for the definition of "mastered":
That said, it said to me that I have 9 vocab and 0 kanji's mastered which definitely isn't true for me, but I noticed that the option above specifically states which vectors not to include, while I up until now treated at as what should be included. I changed my settings now to what is seen above and assume it will take a day for the stats page to refresh/recalculate this (still showing 9 / 0).
Was about to come here to also report back that I am still at 9 / 0 since my post further above - I did in the meantime now also changed the option to not aim for the "average" but "minimum" mastery level 9, excluding selected vectors, but this wasn't 24 hours ago yet. Should this resolve/change something I will report back, otherwise I will just patiently wait :)
While you're waiting, you can test out more of the introduction modules for kanji/vocab. I haven't gotten much feedback on them, so I'd love more, positive or negative! That'll help me the most in getting ready for the release.