Thank you R,
A big part of the problem is that we cannot reproduce it here, under apparently the same situation. I have the same versions here to test and the plugin is working just fine. One of the users has Cinema in English, one in Italian and two in German. I have tried to add Italian and German language packs but it didn't make a change. Other extensions like Google Zync, Substance Engine or Houdini Engine show in the Extensions menu in the failing cases. De normal Console is not showing anything special (I'm not sure if that's the one you ask about). I'm sorry, if I don't give all the information; I'm not the developer myself. I have asked the developer to check the post; maybe he can give more information.