Ad1. yes, think this is kind of bug. Using _task to get pipeline input values is a little bit ugly

Good point, let;s fix it 🙂

new pipeline is built from scratch (all steps etc), but by clicking "NEW RUN" in GUI it just reuse existing pipeline. Is it correct?

Oh I think I understand what happens, the way the pipeline logic is built, is that the "DAG" is created the first time the code runs, then when you re-run the pipeline step it serializes the DAG from the Task/backend.
The initial thinking is that, well we want to sometime in the future allow you to easily edit the DAG in the UI, hence the behavior.
But, specifically here, we want the opposite.
As a temp hack you can add the following:
` print(pipe._task.get_parameters_as_dict())

clear the stored DAG

pipe._task.set_configuration_object(name=pipe._config_section, config_text="") `