I have 3 layers of vectors (shapefiles) that I've loaded into Tilemill. However, nothing is visible in Tilemill. What am I doing wrong, and what should I do to get my map to show up?
This is part of a web app to show the shop floor of a factory. I've built 3 layers in Inkscape, and used QGIS to get it into the shapefile format. I initially had some errors getting Tilemill to load the files, but that now seems to be resolved.
You can see the problem here:

I've looked at all zoom levels, and there's nothing there. When I view a layer's features, though, it seems that there's data:

Thanks!