Just pulled a copy of the code and pushed to a new app in OpenShift. Haven't made any other modifications. As soon as I hit the URL for my app I get a message in the page:
Infinite loop detected in JError
The issue might be wrong database credentials.
The real issue is, that the Joomla! version used here is VERY OLD !!
Question to the maintainer: Would you accept a pull request with an updated Joomla! Version ? Since my pull request #1 was not that successful, I am a bit unsure...
It's actually pretty easy just to push a new vanilla install of the latest Joomla as an OpenShift app, and then set it up via the admin pages when you hit the app for the first time (I just tried this and it worked fine). I'm not sure what additional benefit this project hosted here gives you - since it's using such an old version it's probably best to create a new app using the latest Joomla source anyway.