OPC UA Endpoint - can't create remote tag properties

Hi,

I'm trying to use the ThingWorx OPC UA service but running into some problems. I can create an OPCUAEndpoint thing and connect the OPC UA server to ThingWorx, and in Composer I can see the OPC tags as remote properties under "Manage Bindings", but when I try to save the endpoint thing after adding a remote property I get the following error message in Composer:

"save failed, status: Internal Server Error message: JSONObject["baseType"] not found."

Any ideas why I can't save the remote properties?

Regards,

Greg