Lektor 2.0 (now 2.2) has been released on 11th of April 2016.
A lot of features has been added and improved from 1.2.1.
For Japanese, integration of Japanese translations is important. One of the Lektor's advantage is admin interface is available and designed for non technical people. So it must be required to recommend Lektor for my colleague and friends.
Additionally, my pull request (just one character of translation is fixed) is also merged.
https://github.com/lektor/lektor/pull/184/files
Other details are described in Lektor's official blog.
https://www.getlektor.com/blog/2016/4/lektor-2-released/