DE0-Nano-SoC boot fails

Hi, I wrote already in April 2020 about this to the mailing list. However, the situation did not improve since then. The one and only appliance booting on the DE0-Nano-SoC is Leap 15.0, all newer fail. openSUSE-Leap15.0-ARM-JeOS-socfpgade0nanosoc.armv7l-2018.07.02-Buildlp150.1.1 boots openSUSE-Leap-15.1-ARM-JeOS-socfpgade0nanosoc.armv7l end up at u ends up showing the u-boot prompt: "=>" openSUSE-Leap-15.2-ARM-JeOS-socfpgade0nanosoc.armv7l-2020.02.26-Build1.63 and all newer do not even get to u-boot. Does nobody beside me use the DE0-Nano-SoC or DE10-Nano? Thanks, Christian