If you don't receive to option to free adjust during the process this is probably due to the fact that your SD card isn't large enough to hold the image. (in my case the SD card could hol 3774 MB instat of the needed 3777 MB..) The sollution in my case was found by using a 8 GB SD card and following the instruction in the document. Good luck with the upgrade!
That was exactly it, thanks for the tip!
(BTW: do you know how to restore the missing 4GB from the larger disk? My 8GB SD card now shows only half the size)
I managed to update the software and maps with no problems. Point 24 on the guide mentions the speed cameras and putting the decompressed files into the mapregions folder and they can then be managed through the user menu. I've put the files in the mapregions folder but cant find any mention of them on the menu. Can anyone help?