Try these steps:
Disable "Hide special folders" in CONFIGURATION -> NAS settings -> SMB settings function.
Make sure you are using the RID option in the ADS function set then create a superuser account - Set a Superuser in CONFIGURATION ->; NAS settings ->; Function: SMB settings, you can use this account to set permissions from the ADS server side.
Use the Access Control List from the manual on pages 22-26 and follow the instructions for the Read, Write and Execute permissions, there is notes on page 26 that will help you as well. But for the ACL on the manual set the user for the rights for the share. You can also test by removing the User and Group and Owner rights as well for a mixed environment.