you are right, there is slow but steady development. But no new alpha builds were released on the project page.
It is still up to kartu to decide the when and how.
Though may be I can come up with a kind of monthly "dev snapshots"
But there are some unresolved problems:
300/505 fsk.img size exceeds limits when 7z binary is included
950 hits some internal limits, all apps should be stripped, - needs changes in build.script.
As PRS+ relies on the build in ADE-renderer, which to my knowledge doesn't support right to left, there is no chance to add this feature to PRS+