[eluser]OverZealous[/eluser] @Mareshal
Well, did you try to run the admin.php file through PHP lint (-l)?
Did you check to see if the file was corrupt?
Also, why are you using the CI from bitbucket? Are you sure it is an official version? The latest version of CI is 1.7.2. You might have issues with running a pre-release or dev version of CI.
I can't help you much more. You've basically said "I've installed it, it doesn't work." But it does work. The example app is my main testing ground for DMZ. I run it all the time. Is it configured correctly?
I think the example app still uses short tags, since I prefer them. Maybe you need to enable short tags.
I can't help beyond that. Feel free to update if you figure out what the problem is.