I believe that you’re using our program version for Windows/Mac. In order to add several images from Google Photos to your collage, you need to select “Google Photos” in the Photo Basket dropdown (at the very bottom of the editor) and then drag them into your collage one by one.
Alternatively, if you click the 1st icon along the top right of your image, it will “Auto-fill” the collage, using the first images in the basket.
I hope that helps, but if you have any further questions, please let us know!
Found and thank you very much for the fast response.
I am using the Windows-version indeed, but I opened Google Photos in the startwindow and not in the Photobasket because I did not click on the triangle, but just on Upload – expecting this was given the opportunity to select in the Google windows already opened.