Despite compatibility up to Wordpress 4.0.1, it seems BuddyPress 2.1.1 works fine if Wordpress 4.1 is in English.
Using General_Setting - Site_Language in the Wordpress Admin Panel, if I changed the language to Deutch (German), I immediately got an Internal Server Error after I clicked the Save-Changes button.
After I tried several things, the way to get my Admin Panel back was to delete the files in wp-content/languages.
I got the same Internal Server Error if I changed the language to Nederlands, or Espanol.
If I deactivates BuddyPress, Wordpress 4.1 works fine in German language.
My conclusion is that BuddyPress 2.1.1 cannot work in Wordpress 4.1 in German.
The thing is that I want BuddyPress in German.
Is there any way to fix the problem?
Or, is there anybody who has BuddyPress 2.1.1 working in German in Wordpress 4.1 (or any previous version)?