Upload page

[wppa type="upload"] or use the WPPA+ Upload Photos widget.

Make sure there is/are any album(s) that is/are accessable for upload by anyone.
To do this: set the owner of the album to ---public--- on the Album admin -> Edit (the album) admin page.

For more info on how to make an album for each registered user, see:
https://wppa.nl/members/

The shortcode displays nothing

This means that either you did not configure front-end uploads or there are no accessable albums, or both. The least you can do is:
Select on the Photo Albums settings admin page Table 0 (or Quick setup) ‘yes’ for item 4: May visitors upload photos?

Please read https://wppa.nl/members/ for more info

Here is the simpler instructions page:
https://wppa.nl/docs-by-subject/user-upload/

Finally got all the settings right.
Thanks