[Qgis-user] Problems installing nigthlies (2.11) for testing on Ubuntu/Mint with ubuntugis dependencies

[Bernd Vogelgesang]

Hi,
after a long time, I wanted to help testing, so I try to install the  
nightlies in Linux Mint.

Following qgis.org, I added http://qgis.org/ubuntugis-nightly and   
http://ppa.launchpad.net/ubuntugis/ubuntugis-unstable/ubuntu for trusty on  
a fresh VM install.

When I do: sudo apt-get install qgis python-qgis qgis-plugin-grass
it complains (in german)
Die folgenden Pakete haben unerfüllte Abhängigkeiten:
  qgis-plugin-grass : Hängt ab von: grass-core (< 7) aber  
7.0.1-1~exp1~trusty soll installiert werden
E: Probleme können nicht korrigiert werden, Sie haben zurückgehaltene  
defekte Pakete.


so I tried just installing without qgis-plugin-grass, which ran through.
Though starting QGIS from shell:

qgis: error while loading shared libraries: libqgis_app.so: cannot open  
shared object file: No such file or directory

No idea what to do.
Any hints?

Bernd