I was just using the example projects you provided, there it didn't work. Ok I see only when create a new node can you define the filename and path. I will try that out. Yes the preview export I had found already. Thanks.
But it would be rather annoying to create a new export node each time I want to slightly change the name or path. Why not make it editable IN the export node at all times? And I like to have variations of file exports in batches similar to what you can do in the Affinity graphics apps. what do you think?