Why do I get a white screen when I want to return to Presenter after taking a screenshot?

I'm sorry that you are experiencing this problem! This issue occurs in Presenter on the EntryLine touchscreen (PC module MT21). 

We are aware of the issue and research has now shown that we cannot solve this issue easily. We are currently working on a longer term solution that should make it possible to work correctly with the annotation function on these types of screens as well.