Good Morning Heiner
Well done on getting out even a beta image for this new Pi so quickly . I downloaded the image today and wrote to my Raspbery Pi 4 4GB unit today.
Downlaod went well and image loaded with no issues. I was able to access the online Max2play web page straight away . I then mounted my USB 2 TB HD and loaded the latest LMS image . LMS has loaded and is currently running and updating my Library (which is over 50,000 songs) so will take a little time. Once this has completed will connect the Pi up as my server and will use and report back on how it is working.