To be honest I don't see any difference here.
Now my problem is the following, maybe I didn't make it clear enough above there, so I'll explain step by step.
Before descent I check the weather at my destination airport and set the pressurization to the local ones, but don't activate it, just set the correct value.
Now I'm passing Transition Level, then push the QNH-button to switch the primary altimeter to the local QNH and call for the approach checklist.
My FO says for example "altimeter 1017", I confirm, he answers "Approach checklist complete". That's all fine to me.
Now on further descent, when passing the Transition Altitude of my departure's airport, FS2Crew switches back to standard QNH 1013 calling "Transition Altitude, altimeter 1013" like if I were climbing out. But I'm not, as I'm approaching my destination.
Am I doing something wrong here? I can't see any difference to your explanation.
And here comes my full name, finally:
Manuel Hirsch ;)