I have added a Team Page like the Stuff page in the Tutorial.
Offline this works great but online on uberspace i get an internal server error every time i try to switch between pages in the admin panel. Accessing the same page direct works without a problem.
The Code: https://gist.github.com/glektrik/8b8f455a6892f19fb5e7
The failed ajax request: https://www.dropbox.com/s/p68y361i5d6ygcu/Screenshot%202014-01-05%2018.00.59.png
I enabled the dev mode and php error logging but no errors get logged, my Apache error_log is also empty.
I made a clean install and only added the TeamPage.php file.
When i comment out the line with new UploadField everything works.
@Swaiba: sometimes SilverStripe will report a 500 error on an Ajax requests in the CMS. The link in FireBug will also say 500 error, but often you can find the actual error in the response section of the request, if dev mode is set. I don't know why such an error wouldn't be logged though. A 500 error would also be logged, would it? I don't usually have to check the logs...
@goe: sorry I can't be of more help... I would try FireBug though :)