Hello,
I recall this article https://support.microsoft.com/fi-fi/kb/2774190 once stated that Windows Server 2003 systems and some NAS devices do not understand Resource SID compression and this could cause users getting access denied errors if they attempt to access file shares on 2003 boxes with TGS granted by 2012R2 Domain Controller. Is this true? This article has been revised on September and that statement no longer exists for 2003 servers, only NAS devices.
I'm aware that SID compression can be disabled from Domain Controller if required.