Error occurred while attempting to retrieve message part parameters from a normalized message payload with elements

Hi folks,
I'm back!
Sorry, for being lost for a while but i am running a really interesting project for the last year, a project that combines the entire Oracle Fusion Middleware stack and which i plan to share my experience with you.
Just stumbled on a really simple error so i thought of blogging it.
In case you faced the error stated in the post title (Error occurred while attempting to retrieve message part parameters from a normalized message payload with elements") it's because you didn't specify a reply transformation in your router for one of your process calls.

Stay tuned for some really interesting integration posts!