Hi Stephan -
Did you set up the listener on the Slicer side? You after the C-FIND you need to do the C-MOVE from the PACS to Slicer’s C-STORE which needs to be running and configured as a destination for the PACS. (Or you can use C-GET if supported by the PACS). Once this is all working the studies should show up in the DICOM database and browser.
The code uses CTK classes - this test implements the steps and also shows how to do each of the steps (both the client and the server side) using the dcmtk command line tools and that might help you debug.
-Steve
p.s. while the DICOM networking features do work in Slicer I don’t know if they are actually widely used. DICOM networking is notoriously tricky to debug.