For info for the newbie like me:

When you want to use a Hard disk in the ITGate TGS 100 with the image Juliet 2.0.7a in multiboot, you must firstly format the disk.
But after that you must mount it correctly in the meny Memory Setup (blue button - button 1: advance options - memory setup).
If you do not this the recordings are done in the mmc and not on the hdd!