I checked the manual and the internet for information regarding setting the e-stepper value and there is no indication that one can access that feature. It doesn't mean one cannot, just that there's no information available. It's likely that Pronterface will be of little value to you.

I did discover that there's a new version of firmware (April 2020) available on the manufacturer's web site. I don't usually upgrade firmware for electronic devices unless there's a known problem to be resolved. If your printer has this version, great. I did not research what aspects of the printer are "solved" by the update/upgrade, however.

If you are going to proceed and not concern yourself about the e-steps (no other option, really), consider to reduce your extrusion factor to 0.98 and run a test. Also change the width from manual to auto.