Check watch file in the Right pane for an input file if you want to trigger processing (Run>Auto Run checked) or set it to 'Needs update' (Run>Auto Run unchecked) whenever the input file changes.
Note:
•If you are also outputting to this file in the same .transform you are inputting it, it may cause the .transform to run forever.
•The update may not be triggered if the file is deleted and replaced with a new file with the same name.