d.properties.name actually is a property from states.json, which uses "name". 

A few lines down (https://github.com/KSHSK/WAVED/pull/215/files#diff-9ca43ac74d642dd3e2e8202c6781e78eR145) in the case for ColoringSchemeType.GRADIENT_COLORING is where I think your comment was supposed to go. I'll make another field to choose which field contains the "key" to match with stateName.