First go to "My Publications".
Then click on the little pen icon to edit your magazine.
Go to the "Hotspot Editor" in the left sidebar:
Open "Enrich your publication".
Choose the correct page on the right side and then click on the video hotspot icon on the left side. Click where you want to add the element and drag it open.
You can now configure the hotspot on the right side. If you want to use Youtube or Vimeo choose the platform you want under "Source". Then add the ID of the video you want to add. How to get the ID:
If you want to upload your own video, choose "Yumpu" as source and then hit "Select media".
Please note that the size of your mp4 video shouldn't exceed 100 MB.
Click on "Upload Files" and choose the video. Then click on "Insert".
That's it! After you hit "Save" the video will be in your magazine.