I noticed that some list operations like "shift list"change actually the data tree. For example it adds another subbranch to it. Could anyone tell me why that is and how to avoid it without using the path mapper all the time.
Sorry you can’t. This is working as designed, as it is possible to provide more than one Shift integer in which case every input list results in multiple output lists. I realise this is a very rare case for the Shift component, but the path logic needs to be consistent across all components.
You can enable the Simplify or Flatten option on those parameters you know for certain can be simplified/flattened, but that is not a solution that works in all cases.