We will need to adjust the naming of our polygon files.
From source code...
// If set to 'hex' then GeoJSON files are assumed to be named like
// 'YYYY_MM-<resolution>.json', where 3 files exist for each of resolutions
// 'low', 'medium', 'high'. If anything other than 'hex', then this value is
// the MMMM_YY- suffix to look for. For example:
// If set to 'city_council_districts', then the system will look for
// GeoJSON files like 'MMMM_YY-city_council_districts.geojson'.
var polygonType = 'census_block_groups';
We will need to adjust the naming of our polygon files.
From source code...