Start importing the course from the old Composer to the new one from the old Composer page. Download the XML file of the course to your device via the properties view. Once the XML file is fully downloaded, go to the new Composer side. Please note that the maximum size of the XML file must be 1GB in order to import it into Prewise Learning.
Click on the "Import Gimlet Composer" button in the top left corner of the course listing view. If you want to change the name or language setting of the original course, you can do so using the form that pops up. Then select the theme you want to use in the course interface. Finally, click on the XML file radio button and select the XML file you just downloaded from your device. Finish the import by clicking on the import button.
You will finally receive an acknowledgement of the successful import and any comments on page-specific compatibility issues, if any.