Drag and drop the exported JSON file to the viewer.
and import it here (by dropping the file onto the viewer)
I tried this, and got this: (shorthened for space, and no pic at all.
{ "type": "FeatureCollection", "features": [ { "type": "Feature", "properties": { "id": "values", "roadWidth": 0.00007207207207207208, "towerRadius": 0.00006846846846846847, "wallThickness": 0.00006846846846846847, "version": "0.7.4", "riverWidth": 0.00030589267170456956 } }, { "type": "Feature", "geometry": { "type": "Polygon", "coordinates": [ [ [ -0.011786272398350993, 0.0007293488994151453 ],