When using the «Open in Excel»( Dynamics Office Add-in) feature in the New Dynamics AX RTW, you may have some trouble opening it in Excel.
Especially if you have a corporate login, like me. It then seams that the login failed.
Microsoft have upgraded the Dynamics Office Add-in, but on existing demo data (Contoso) may also need to be changed.
Then the connector seams to be working (At least for me)
Also take a look at https://ax.help.dynamics.com/en/wiki/office-integration-troubleshooting/