File list widdget not working

Hi Renzo, I managed to install your firmware on a "Wemos D1 mini" and almost everything works as it should :) There seems to be a problem with the File list widget, it shows a spinner and no files are listed. As soon as I access the Storage from the menu there is a "3D Printer disconnected" error. It shows a "3D Printer connected" message after that but there are no files in the list :| Any idea what is causing this problem ?? Thanks, Rainer