I added
                if (SandboxGameAssemblyWrapper.IsDebugging)
                {
                    LogManager.APILog.WriteLine(ObjectBuilder.TypeId.ToString() + " (Property Set): Setting custom name to '" + value + "'");
                }

To the set {} when you set the CustomName property on a terminal block.  You can see the issue below:

2014-09-02 08:07:42.127 - Thread: 22 -> MyObjectBuilder_Beacon (Property Set): Setting custom name to 'Shipyard status: Constructing 'BasicMiner'.  Time left: 0d:0h:1m:3s'
2014-09-02 08:07:42.175 - Thread: 10 -> BeaconEntity (InternalSetCustomName()): Setting custom name to 'Shipyard status: Constructing 'BasicMiner'.  Time left: 0d:0h:0m:3s'
2014-09-02 08:07:47.160 - Thread: 22 -> MyObjectBuilder_Beacon (Property Set): Setting custom name to 'Shipyard status: Constructing 'BasicMiner'.  Time left: 0d:0h:0m:58s'
2014-09-02 08:07:47.194 - Thread: 10 -> BeaconEntity (InternalSetCustomName()): Setting custom name to 'Shipyard status: Constructing 'BasicMiner'.  Time left: 0d:0h:0m:3s'
2014-09-02 08:07:52.210 - Thread: 22 -> MyObjectBuilder_Beacon (Property Set): Setting custom name to 'Shipyard status: Constructing 'BasicMiner'.  Time left: 0d:0h:0m:53s'
2014-09-02 08:07:52.226 - Thread: 10 -> BeaconEntity (InternalSetCustomName()): Setting custom name to 'Shipyard status: Constructing 'BasicMiner'.  Time left: 0d:0h:0m:3s'