Thanks Simmy for your answer.
Sure, I clicked on the VCT2000 symbol, which opened a dialog box to start the process.
The EGR is working as it can be seen from the charts. My suspicions about a miss-alignment are indeed based on those charts...
SNAG-003.jpg
SNAG-004.jpg
Another thing I should have mentioned, is that performing the same command with engine stopped but with ignition key in pos II returns a successful message, instantly, but without any noticeable movement / noise at the valve servomotor.
And last but not least, I'm currently using a J2534 interface, not an original DICE. Could this be an issue ?