Create folder that can't be deleted, but users can do everything inside

Hi, from admin acct I have created a group folder “Share” using the “group folder” app. Then, from User #1, I created a folder named “Documents”.

I’d like User #2 to never delete “Documents” folder created by User #1. Also, I’d like User #2 being able to access/create anything inside “Share” folder (and delete what she created), but never delete what User #1 created, and to access/create anything inside “Documents” folder (and delete what she put inside of it), but never delete what User #1 created inside “Documents” folder. So, what would be the permissions for the “Shared” folder to be set under the “group folder” app, and what would be the permissions set by User #1 using the advanced permission management? (a bit like how /tmp/ folder works)

In “UNIX” term, we’d use ACLs/sticky bits. Can we do that kind of things with the group folder app + advanced permissions settings…?

Also, how should we understand write and create? Like write inside a file (i.e. edit) and create for creating a file and directory?