This is my solution for the July mission.
First I checked the box that the workflow is triggered when new items are created.
Second thing I noticed was that the XML that was read from the form variable was always encoded, so I decoded it.
Now the XML looked fine but the workflow still gave me the error
The workflow could not update the item, possibly because one or more columns for the item require a different type of information.
So I had a closer look to the update item action and found that the default lookup type "Type 1" was lacking a #
So instead of
I made it
Now the items were exported successfully