The Dur parameter relates to the duration / length of the result after processing. I think I’ve manually limited the duration in the definition file as I figured a max 25 second output should be sufficient, though this is of course subjective. If you need longer results you could try and change the definition file for this particular process in the scripting terminal for the CDP tool.
Take note that this process needs a mono file as input, so if you are not getting any output this is the first thing to check.