Bump.
I am having a similar issue - new build, attempting to update the Commaner Core that came with my h150i elite capellix 360mm, but the mandatory firmware (2.6.201 mentioned above) fails to install each time. Additionally, as soon as the update fails, the AIO fans and the additional SP120 RGB ELITE that I have attached to the core ramp up to max speed until I shutdown and reboot my pc. Any help would be greatly appreciated! I have exhausted all options suggested to me by tech support thus far and I am starting to believe the only fix may be to manually install the firmware but unfortunately, I do not have access to the .hex file.