Support Staff2 Posted by AJ on 20 Sep, 2012 09:22 PM
This is definitely a bug, and it appears to be caused by the
projection of the file. I'll pass this along to the developers to
As a workaround for now, you can reproject
your data to Google web mercator before bringing it into
TileMill. I did this with your M shape file to make sure that
worked. You can use the attached copy if you want.