Test does not accept question

Hi there,

first of all thank you for your very useful plugin.

I’m in construction of learning lessons and tests and do have a very strange problem. Adding questions to a test I had problems several times when there are more than 17 questions already added.

Is there any reason why this could happen. Perhaps the amount of questions are limited? I would try to get the reason for this but do not know exactly where to begin.

Thank you for your help.

Ron