Description of problem:
In the data modeler, there is a 'create' button in the editor that allows you to create data classes and objects. There is also a 'create' button in the header area next to 'save' and 'close window (X)', which confuses users since there is already a create button in context of the window. Remove this button in the header bar and leave the create buttons in the context of the modeler screen.

Image showing what to keep and remove:
https://www.evernote.com/shard/s230/sh/87c28f32-bbe5-42df-8a27-0dc81b09b980/bc07ce0c9fbb7e30729c9e55d466ed1c