If you are trying to map multiple incoming messages (schemas) to a single outgoing message (schema), you need to create a new map within the orchestration. Here are the steps:
- Create an empty orchestration.
- Create all the message types you need (all the input messages and the output message)
- Drag a construct message shape and a transform shape onto there.
- Configure the transform shape and add all your input messages to the Transform Source list
- Set the output message as usual and click OK
- A map file should appear in your project. Open it
- You will see on the left-hand side all your input messages are now available in the mapper (under Root/InputMessagePart_1, _2, etc)
You can then rename/move the map as needed.