Changes
A new [[MetaClass]] has to be created as a derivative (child) from another class (parent). This can easily be done in the [[Class Browser]] control, therefore
# Navigate to the favoured parent [[MetaClass]] inside in the {{Class Browser}}control# Create a new child MetaClass via ''Derive new object'' from the context menu
# Open the [[Object Editor]] control
# Set the newly created MetaClass as context object to this control
