To update a screen in Marvel which was created using the Sketch plugin:
- Open your design file in Sketch
- Select the artboard you would like to update > make changes to that same artboard > click the Sync Selected button (alternatively you can click Sync All to send everything)
- The export settings menu will appear, select the project you want to sync to and the image size
Note: Each artboard is unique, even if they have the same name. If you create another artboard, it won't sync with the original even if it has the same name. You'll need to edit the original artboard to sync the changes.