Within Teamwork Projects, you can export the Gantt chart related to your project to either Microsoft Project or Gantt Project.
You can do this by clicking into the 'Tasks' area:
Within the left pane under reports select 'Gantt Chart Export':
Once you select this you will be presented with an option to choose the export type you wish:
Note: The exported file types are .XML for Microsoft Project and .GAN for Gantt Project.
For more information, see: Gantt chart