Hi Dykarna
I had the same problem and I just found the solution.
Your language files are in the right place at http://vaxmora.se/wp-content/languages/bbpress/
But you need to rename the files from this:
bbpress-plugin-sv.po
bbpress-plugin-sv.mo
to this:
bbpress-sv_SE.po
bbpress–sv_SE.mo
Then you should be good to go. Worked for me.
And by the way, thanks for leading me in the right direction.