"you can create a question with several right answers and no wrong answers"
-- How? I don't see a way to designate a question as ungraded, to give +100% value to more than one answer, or to make an essay or short answer question which is correct by default.
Multiple-Answer questions have to have answers that add up to exactly 100% of the possible points, so I can't just make every answer worth 100%. I want them to get 1.00 pts for ANY answers checked.
Attempts to value an entire question at 0 points result in error messages or defaulting back to 1 automatically. Essay questions might be a solution, but they must be graded manually by a "Teacher" role. It is problematic because the student is given 0 points on an essay question as the default, so they would get a very disappointing grade and "Try again" message until the question is graded manually. I'll keep looking though.