H5P

Hello again, Stuart!

We finally managed to resolve the problem. Our developer spent about his whole afternoon debugging and finally spotted the issue:
In our php.ini, the value for "max_execution_time" was way too short, leading to writing processes to /temp being disrupted. Sessions were also corrupted within the process. After raising this value from about 30s to 300s, everything works fine.

Cheers and thanks again for your time and insights