@kus_kus. Thanks for posting your questions. I will answer them as best as I can:
2) I do have ACL implemeneted. So, you can specify the access levels for each file or listing, whether it is Public, Registered, Special or whatever you create. To be honest, I am not too sure what you mean by “change access rights per different groups of groups”.
3) Yes, direct links to files are hidden. Please look at the demo for a preview.
Hope my answers have helped you.