Yes, it looks like you will need to have some custom work done to support this. The built in connector is a combination of a regular TCP socket Transport and a UTF-16 based Adapter (parser). The Transport hands raw bytes to the Adapter for parsing. Since the Base64 decoding process converts bytes to bytes, you could potentially swap out our built-in Transport or Adapter depending on which one you wanted to preserve. For example, if you think the built-in Adapter is really nice, you could write your own TCP transport that automatically decoded the bytes. Or you could use the built-in TCP Transport and write your own custom Adapter to decode the bytes and convert them to GeoEvents. Either way, there are code samples in the SDK showing how to write a custom Transport and Adapter.
