Cannot resize Entity shape in a database diagram.

[MikeDCDBA]

I am new to Viso, and have recently reverse-engineered a SQL Server 2000 database that will be migrated to SQL Server 2008 R2.  I cannot change the height (or resize in any way) of any of the Entity shapes.  I cannot drag the handles of a selected shape, nor can I modify the height using View | Show | Task Panes | Size & Position.  I sure it's something simple. I checked the layer properties, and Locked is not checked.

Thanks,
Mike

[Paul Herber]

Have you checked the individual shape protection
ribbon Developer -> Protection.

(you need to be in developer mode to see this
ribbon File -> Options -> Advanced -> General section
)
Why on earth is this hidden in developer mode??