Hi Christoph,
So we are in same boat. 
Pity though, I have more than 200 fields in mapping and not one but several fields where I have to rely on data in structure, being processed later. Maybe will try to ask my PI colleague to create some simple transformation of names at PI side and forward them to AIF as 01_SYSTEM_INFORMATION, 02_VEHICLE_INFORMATION, 03_ORDER_DOCUMENT.
This can be a workaround. Hope AIF developers will provide better solution with one of the updates.
Regards,
Petr