I Wrote Samsung Support to complain and got the reply that they will put a better working update tool on their website very very soon. I received that answer today May 28 2014.
They will email me when that firmware update tool is released.
My sytuation: iMac early 2008 with Samsung EVO 250Gb SSD and HD Caddy with a 750Gb HDD in place of the Super drive and the superdrive mounted in a external USB housing.
Fusion Drive enabled.
Works like a charm but I really would like to update the Firmware and be able to update it in the future.
I tried everything from running Windows on the Mac using VMWare and using Magician to update the firmware, doesn't work, Install Windows on a external USB HDD and trying to do it that way, doesn't work.
The only solution right now is to remove the SSD, mount it in a Windows machine, update the firmware and build it back in the iMac.
I will give Samsung some time to supply the new and working update tool before I take the iMac apart.