Thanks Colin!
I think I got it, but I have to make absolutely sure that I understood it right...
The following is possible?
level 1 restricted collection (up to 100)
- level 2 restricted collection (up to 100)
-- level 3 restricted collection (up to 100)
--- level 4 restricted collection (up to 100)
---- level 5 restricted collection (up to 100)
It does not mean that in all levels together below level 1 there are maximum 100 restricted collections allowed in total?
level 1 restricted collection (up to 100)
- level 2 restricted collection (counts to the top level 100)
-- level 3 restricted collection (counts to the top level 100)
--- level 4 restricted collection (counts to the top level 100)
---- level 5 restricted collection (counts to the top level 100)