Nginx-proxy.
Mustafa, we waste too much time back and forth - I support KloxoMR, I have been around prior to the tragedy of Ligesh and Kloxo being open source. I am trying to help. I am good at what I do. I do not know everything, and look to others when need be. You have saved me before, and I have figured out things for you.
My suggestion to you is this, so you don't have to rewrite entire file manager.
1. Display only files owned by the client logged in.
2. Sanity check permission editor to only allow changes from owner
3. Sanity check any file being saved, must be owner.
if logged in as admin, under server file manager, allow all files and all changes (no restrictions).
It is 6am in US, been awake all night with this, please consider my suggestions, they would not be so hard to code.