XPrivacy - explanation of restriction settings Maybe it's me but I don't understand XPrivacy's per-permission-settings.
The legend sais 


first check box: restrict category or function
second check box: restrict on demand
first check box is default value
■: stands for "partly restricted"
?: restrictions will be asked


But what does ✔ (checked) mean? Fully restricted? And what are the meanings of the combinations?

And what is the "default" case for?

Can you explain the following combinations:

[ ] [ ]  (no restrictions (the only one I truly understand :)))

[ ] [?]  (?? default: no restrictions but ask otherwise?)

[ ] [✔]  (?? default: no restrictions but full restrictions otherwise?)

[ ] [■]  (?? default: no restrictions but partly restricted otherwise?)

[■] [ ]  (?? default: partly restricted)

[■] [■]  (?? partly on demand, default is partly?)

[✔] [ ]  (?? default: fully restricted?)

[✔] [?]  (?? always restrict but ask otherwise??)

Which ones are missing?

Why isn't there a combination like [■] [?] or [✔] [✔]?

Please help me out..
According to the README file of XPrivacy that can be found here:

The tri-state check box works this way:
unchecked = no items in the category are restricted
solid square =
some items in the category are restricted
check mark = all items in
the category are restricted
Note: By default, categories and functions
are filtered by permission, so you may not see all of them. The check
box state is independent of this.