Another n00b problem for me. When I am trying to install some applications (these are Helium and Pushup from appsformeego repository) from OpenRepos with Warehouse to my N9 I get the following error:

E: Sub-process /usr/bin/dpkg returned an error code (255)

And the apps don't install. For Helium I tried also the rzr repository in OpenRepos but no luck there either.