Load your model using the ruby bindings in a terminal (see Optional - Install Ruby section in the introductory tutorial) or create a very simple measure in which you'll run this loop to remove all ZoneMixing objects

model.getZoneMixings.each do |mix|
  mix.remove
end

Load your model using the ruby bindings binding in a terminal or create a very simple measure in which you'll run this loop to remove all ZoneMixing objects

model.getZoneMixings.each do |mix|
  mix.remove
end