I would not even use the XML file to copy the effects between songs, it's easier than that.
I would first open the sequence with the Megatree, use the XL/NC as if it were Excel, highlight the effects column and do a Control+C.
Now open the sequence with the Arches, add a display element - Megatree, highlight the first cell of Megatree and paste - Control+V. Save and enjoy!