This seems an odd request, but we developers often get weird requirements I guess. There are two ways to approach this. Since you already have your file created, you might not want to try and recreate the logic in your tAdvanceOutputFileXML and put it in a tXMLMap. If this is the case you can write the file, read it in as a single String using something like tFileInputRaw and then use the code below in a tJavaRow to remove the offending characters....
output_row.content = ((String)input_row.content).replaceAll("\\r|\\n", "");
Alternatively, to do this in one go and then create a file, move the logic into a tXMLMap. Connect that to a tConvertType to convert the output from XML to a String. Then use the logic above. Once that is done, write the newly formatted String to a file.
