sorry for the late reply. Didn't got notified - or precise: got notified but mail was tagged as spam...
As I didn't have a lot of QlikView experience I didn't thought of that way. But tried it an the first test seems to be working. Created a button with a start trigger and then for the trigger:
parameter: /c start sapshcut.exe -system=XXX -client=100 -language=YY -reuse=1 -type=Transaction -command="*KS03 CSKSZ-KOSTL=40620;"
As a result the correct cost center was called in a new SAP session. As the parameter can be edited as a formula, I'm sure that it will be possible to extract the selection into the right places of the formula.
Thank you very much.