Hi Bill

Thanks for posting on the community! Unfortunately there is not a way to turn off this behavior. However I understand how this feature would cause difficulties when creating your diagrams. Would you mind adding your idea to our feature request form? Ideas submitted to this form are passed on to the product development team for their consideration.

In the meantime you can undo the auto-enumeration by clicking CTRL + Z. 

Thanks for your request and I apologize for any inconvenience this causes you.

This dash to dot action for UML class diagrams is very frustrating and distracting.

Hi Craig 

Thanks for continuing this thread and for your feedback! I understand this functionality can be really frustrating and would encourage you to promote this improvement idea to our development team through our feature request form. The more people who request this feature the more likely it is to be prioritized and built out. Thanks!