There is a Download SVG with Google Map button on MapSVG start screen. What does it do?
If you want to overlay an interactive vector graphics on Google Map,
you need to download a calibrated SVG file with Google Maps screenshot, edit the SVG file
in https://inkscape.org and then upload the file back to MapSVG.
Your vector graphics will be automatically overlayed on Google Map by MapSVG.
See more information on the following page: mapsvg.com/docs/tutorials/google-and-custom-svg
