Backport of Cross Section machinery fixes to 72x

Backport of fixes/finalization of cross section machinery that are already in 73x and 71x.  Also backport GenJet configuration change from 73x (already in 71x)
What do you mean?  old setting is true, new setting is false.  This is the same change which has been made for 73x and 71x.  Did I miss something?