Private Share Access Permissions on Active Directory Joined EX4100

We have an EX4100 that is joined to our Windows domain and on the latest firmware (2.31.204). When creating a share and making it private (toggle the Public setting off), we assign the desired access permission to the users who need to access that share and leave the remaining users listed with the default Deny setting. Domain users that were assigned read or read/write access are given an ‘Acess is denied’ message and prompted for credentials. Providing anything other than a local NAS account with access rights gives the ‘Acess is denied’ message repeatedly.

We can successfully login to the web portal with AD user credentials, so the AD connection does appear to be functional. What are missing to have this function for shares and AD users access?

Looks like the below is the answer and well it is very unfortunate. For example, my account is a member of 32 groups in our AD implementation so to get me working for 1 share using the AD account I have to go into 32 groups and give them the necessary access, then into the share and give my specific account the need rights. 33 actions for 1 share. Big miss by WD in the default being Deny vs undefined permissions.