Nothing jumps out at me. You may want to double check for odd use of
"&" or "--" which may cause issues.
If you header line were wrongly formed this might also cause it to
drop out, or there might be an issue that is related to the particular
way you are mapping to the Commons template.
I suggest testing by cutting down your test set to, say, a basic 3
records and testing it on beta. If that does not work then by all
means share the 3 record long xml file here and we might spot
something.
Fae