Scenario: Create 'user1' with full permissions of uploading/deleting/modifying files from a sub-user (child) 'user2' home folder.

Example:

user1 - master user account - able to see user2's files and sub-folder and also modify them
user2 - child user account - only able to download files without the permissions to upload or modify existing files

The restrictions for user2 can be applied using the Admin GUI->Access restrictions (Upload and Filesystem Restrictions).

First and foremost you would need to build the two user home folders in the following way:

/homefolder/user1/ - this will be the home folder for user 1 who is going to have full access on the files and folders
/homefolder/user1/user2/ - this will be the home folder for user 2 who is going to be restricted

Next you would need to assign (and create) a new User Class for user2 from Admin GUI->Accounts->User Classes, for example: 'restricted'. You can match the user by either its username, group ID or IP address.

Once you have user2 assigned to a specific User Class you can then go forward with the restrictions which should look as follows:

Admin GUI->Access->Upload Restrictions:

Upload Directory: /*
Allowed: No
User Class: restricted
Owner and Group: *
Mode: blank

Make sure to enable the entry once created.

Admin GUI->Access->Filesystem Restrictions:

Operation: Delete a file
Allowed: No
User Class: restricted
Path: /*

Make sure to enable the entry once created.