If the Vamtam Offline Jetpack plugin is activated and you still don't see the Portfolio and Testimonials sections, please check if the Custom Content Types (Portfolio Projects and Testimonials posts) section in Jetpack > Settings is enabled:
How to upload or recover the Testimonials and Portfolio posts
Finally, if you need to upload the testimonials and portfolio posts, please download the attached files (click with the right mouse button and then Save As XML) and import them into your installation following the steps below:
Dashboard > Tools > Import > WordPress
If you haven't installed the WordPress Importer plugin you'll see an error. Please proceed to install the plugin:
Please choose the import file, then click on the "Upload file and import" button.
Please assign posts to an existing user - choose from the drop-down menu. Please make a tick to "Download and import attachments" and click on the "Submit" button.
You'll see All done! on your Dashboard, if everything is imported correctly: