Simple File Transfer with Transformer

I'm trying to transfer a simple .txt file to an FTP Site - Mirth 3.1.



It works fine except when I try to add a transformer I get the following:



TypeError: The content of elements must consist of well-formed character data or markup.



I assume I need to change the datatypes but am not clear on the best approach.



Transformer is simply a conversion of line endings : msg.replace("\r", "\r\n")

Simple File Transfer with Transformer