Is it possible to award points for completing all tasks in a stage? What if there are multiple types of tasks?
in general there is no such option.
But the following workaround is possible:
Create a new stage and a new quiz element right after the stage you want to link it with. Now choose multiple choice as quiz-mode and type in two possible answers (e.g. 1. Earn extra points 2. Waive extra points). Tag the first as the right answer.
Next, put a Switch on the new stage (https://en.actionbound.com/stepbystep?setlang#switches).
As conditions set „Players“, "then „Points reached so far“ and add either the maximum amount of points possible in the stage before or less points if you want to be ab it more fair
Furthermore you have to add another stage after the one with the Switch to keep it separated from later elements.
I hope this may solve you issue for now.