Quiz

I am wondering about tags and course tags for Quiz questions.

1. What is supposed to be the difference between tags and course tags?
   
2. When I click on any tag assigned to a question in the question bank, I get to a page saying "No results for '...'". Is that normal or to be expected?
   
3. Say I have a Quiz question in a course category. Then I assign a course tag to that question from within one course belonging to that category. Then I switch to another course in that category and look for that question in the question bank. What I see is the question with the newly created tag being displayed next to the title. Why do I see that tag? In the popup under "Manage tags" for that question, there are no tags listed, which one would expect, I guess.

Can somebody shed some light on these issues? – Thanks in advance!