Can´t install UTM9 on ASG120 rev4

I tried to install the new UTM9 on my ASG120 rev.4 and got the following error:

"[ 1.257671] drivers/rtc/hctosys.c: unable to open rtc device (rtc0)
INIT: version 2.06 booting"

Installing it with "classic" mode works w/o any problems until installing the system.

Then it aborts w/ the error that it couldn´t found a specific file/image on the CD-R.

Installing the old Astaro v8.301 worked w/o problems. Later v8 has the same error.

Does anyboday knows how to get rid of this error and installing a fresh UTM 9 on it?