I use the same approach of the tutorial (Messaging) to personalize the AutoShowSavedMessage but it not works.

After create the Message I put the code in the BeforeDelete of BO.

Can you please indicate me Where the code should be and a sample of the code?

Regards

Try just using the form AuoSaveChangesMessageKey property. Type your message key there, and leave the AutoShowSaveChangesMessage as True.