Robin,
I tried another computer (Windows) for creating the SD-card and it fails in a similar way: the process of "physdiskwrite" stops after just a couple of minutes with an error message (the error is non-specific: just "error").
I re-did all steps from the begining: download the image, extract, checksum,..., etc. Everythig goes OK until the physdiskwrite errors.
-- Mihai