Hi, guys!
This is my first post on this site. I decided to try to help those who haven't took the exams yet.
I'm from Russia and we have 2 embassies in Moscow and Vladivostok. But this year for the convinience of the participants tests and interviews were also held in Yekaterinburg city (central Russia). So basically there are 3 different groups of candidates for the same ~10 spots, concidering the fact that there were about 30-70 candidates in each city - it gets pretty tough, eh

In Moscow there were about 60 candidates, this number was cut down to 30 after the tests.
In Yekaterinburg there were 40 candidates cut down to 10.
Vladivostok (as far as I know) hasn't took the exams yet.
The tests in my city were on Saturday and we had an interview on Sunday, so it took them 1 day to check the papers.
Most part of those who made it through the tests in Yekaterinburg had N2-N1 levels. And with that, there also were 2 people with insuffitient Japanese: a girl with a research in Medicine, who knew only kanji and didn't even bother to try the grammar part and a guy with a research in Astronomy and Astrophysics, who had N5 level. Both of them passed the tests and were invited to the interview! So i guess the language profficiency is more of an advantage, and is not that much of a game changer in case they like your research.
They try to consider everything: the research plan you've prepared, tests results, the way you look, the way you talk and behave.
The tests were quite challenging, even the one in English was a bit more difficult comparing to the previous years. But if you have intermidiate or better level of English, you'll manage it. As it's been mentioned, the texts in the 5th part were about food waste in the UK and self-determination. So maybe you can try learning some lexis or reading similar texts in the internet.
Now the interview details.
It was held by the panel of three people. The questions were logical:
- Why are you interested in Japan?
- How can your research benefit Japan?
- Why do you want to do your research particularily in Japan?
- Have you ever been to Japan?
- Aren't you scared of living in a foreign country with different culture and traditions?
- Which Universities have you chosen and which professors do you want to work with?
- What are your plans for futute?
Well, basically that's it.

I hope this information was useful! Wish you tons of luck!:woot: