Starting from the Home Page in PathoTrainer, navigate to Slides and Images in the sidebar and select the Inventory tab. This will open the treeview of available sources of slides, for example from the PMA.core instances you have linked to PathoTrainer.

From here, you can navigate through folders and view the slides and images you have available. You can:

Hover your cursor over image files to see a small thumbnail

Click on an image to open it in the larger viewer