You should probably edit permissions on who can create new files in /home/troinof/www/var/.
Not sure why it is needed though.
I’m using freebsd and distillery for packaging releases and my /home/idiot folder doesn’t have anything related to elixir or erlang … I start the app in /usr/home/idiot/my_app if that helps.
Oh, and /usr/home/idiot/my_app/var contains WARNING_README file.