Roel,
Just hang in there a bit longer, I'm sure your SD1 will arrive soon... And it is definitely worth the wait.
I purchased the PC cable & software ($15 USD) for the X1 previously when I had the X4. The software could also be downloaded directly from Ketron's web site under software downloads. There are 2 parts, the XPC driver and the XFT file transfer software. The software is written for X1/X4 and I don't know for sure if it is compatible with SD1. I expect Ketron to release one for SD1 soon. I have downloaded all the files from all folders in the SD1. But I have not tried uploading until someone can tell me that it is safe to do so. I don't want to mess up the hard drive. There are 16 demo songs and the downloaded midi files played perfectly in my PC except some of the sounds did not map properly.
The cable could easily be made if you know how to do it. It's D-9 serial female to DIN 8 male. For 15 bucks, I didn't want to bother to make my own cable.
Henry