Flashing Rock Pi S Failed

Hey everbody,

its a Rock Pi S with 512 MB with 4GByte NAND Flash (D4n32). (Hardware Rev 1.3).

When installing (Windows) with RKDEVTOOL v2.81, the device is going into a boot loop. Just tried with a lot images, but with no success.
(Ubuntu, Armbian and Debian is failing).

Best regards