Hi all,
An addition to my previous post: I just tried copying the dump file through a USB-cable connected to the camera, and it worked! However, when I try to copy the file through the card reader, I still get the error message. Very strange, and I'm not 100% sure if it's CHDK, Windows, my SD card reader, maybe a combination or whatever.... What does matter is that I'm capable now of getting the dump to my HD :-)
Thanks!
TheJez