I'm trying to change the Stream property inside a DTL with a Source Class of Ens.StreamContainer. The code, below, will change it within the DTL testing tool, but running an actual message through the Production's Process doesn't change the Stream property. I can change other properties of Ens.StreamContainer by using the normal Set action and it is reflected when running it through the Process. For context, this uses a FTP service to grab a file. Any thoughts on why I can't just write modified stream data to the Stream property?