Select the node PARTsolutions Exporter.

Under Preview Settings, click on ....

-> The dialog box Select options is opened.

Here you can select different options for the generation of preview images (directories, projects and products (lines).

For directories you can also choose the view "2x2". Then the first four previews of subordinated directories or projects are grouped.

Preview images generated in the "grouped" mode

Move the desired generation options to the right under Selected Items.