Tend to agree with Dave_3.0 based on the point in the referenced thread where it is said
"The xml file must have simple non-hierarchical structure so for eg. users remove groups, rights, partitions, OBS etc."
For project Custom attributes is similar
and
"If you have a simple set of existing data which creates single level xml and you want to add data/records then this is at its best."
Watch the video to see how smooth it can be when it works.