The Domain Controller on the server is running on a virtual machine called ZDC and uses the Microsoft Windows Server 2012 R2 Operating System. You can find out the IP address of the ZDC virtual machine from the Commissioning Console. (This Virtual machine has an IP address with the last octet being .144)
Use Remote Desktop Services (RDP) to connect to the ZDC Virtual Machine, and you can then run all the standard Microsoft tools from the Administrative Tools folder. (eg Active Directory Users & Computers)
You can use a local domain admin account, or your Management account to log in to the ZDC virtual machine. If using your Management account, you must use the ZCP domain prefix with your username to logon. Eg ZCP\username.dfg.
You can customize Active Directory however you like, including creating and editing Group Policies, OUs, groups and objects. However, it is strongly recommend that users and groups are kept in the default Organizational Unit for each server which is:
[ Active Directory Domain Name ] > Zynstra > Cluster ID.