Take existing Electron App, amend UI, tweak final output

I have a Javascript/Python created Electron produced on Mac OS X that I require the UI updating, code checking and slight tweaks to the final output.

The requirements of the application is to take a Word Document, export it to TXT and then have the User visually catagorise the input to produce a final, structured XML file.

This is to be used on Mac OS X only, and it currently works, I just want to finalise it, make it look and feel more professional and structure the final output better before sharing with my client, so they can get structured input within an XML.

This is now an urgent project, and would like to discuss and agree requirements and timings on a call.