How to firmwareupdate a Conductor?

I download the latest UpdaterAtor. I download the latest Firmware to my Conductor. I try "Make Image USB Stick" and "Generate Upgrade USB Stick" to a 8GB USB-stick (Nomad software stick from ETC), I just get stuck on a lot of errors for missing files.

Read that it does not work to upgrade from 2.0 to 3.0, so I should first start by upgrading to 2.1 before moving on to 3.0. But I think this is only when i "Generate Upgrad USB Stick" because Image USB is a Clonezilla and shuld rewrite everything on my Conductor?

Is there any special USB-port I should use on my Conductor? Is there any "special" formating on USB-stick I need to have? Is the size on my USB-stick an issue, all files fit in my stick?