It seems to be a path issue, because on the Raspberry Pi I deleted the folder gladysassistant_OWON_test that had been created when I set up my test instance and now I can no longer access the z2m interface (http:adresse_ip:8080 returns: unable to access this page).
I need to be able to say somewhere that they should go look in /var/lib/gladysassistant
Edit: I thought I