Interactivity> Gap Fill
Dutch problem.
In Dutch, the comma is used extensively in texts, but very much in mathematical assignments. In Xerte, with Correct Answer, the separator comma is used for correct answers. When creating an Interactivity> Gap Fill, it is therefore always important to replace that comma with, for example, a tilde (~).
By default, could the comma at Correct answer be replaced by ~. That can prevent a lot of problems.
Ronald