How did you load the locations? Did you load them one by one manually or using ProPack (I do not see ProPack so assume you were adding therm one by one)
If you have incorrect data that Google cannot geocode then your address may be incorrect or some of the fields are missing and there is not enough info to process the query.
Do you have a theme that is updated to be compatible with WP 4.5.2? SLP maps are javascript intensive. Unfortunately I cannot troubleshoot for you since the url is your dev site. Here are some suggestions about geocoding erorrs