Easydiscuss ACL settings: some doubts

Hello,
I ave some doubts about the ACL settings
(not the category ACL, the main setting: https://mysite.com/administrator/index.php?option=com_easydiscuss&;view=acls)

Do the settings of a certain user group affect all the children groups?

And if not, what happens if a user is in more than one group and settings are different for each of them?
This is the first time I look into this and I noticed for example that:
Group A > is allowed to vote replies
Group B > is NOT allowed

and I have several users inserted in both groups.

Also, I am not sure I uderstand how these main ACL settings interact with the single category ACL settings.

Thank you