Create makro that counts the number of checked tick boxes in a survey

[johannapaj]

I want to create a macro that counts the number of checked tick boxes. The basic idea is to get a survey with tick box questions, where the maximum numbers of checked boxes is fixed. For example; among 10 questions, can the sibject only check 5 of the 10 tickboxes. When the number of allowed checked tick boxes is exceeded, a text should appear saying that the maximum number of checked boxes is reached.