Reported for: Toolset Maps 1.8.1
Resolved in: 1.8.2
Toolset Maps 1.8 and 1.8.1 require MySQL 5.7.6 and above to provide distance filtering and sorting capabilities to Views. We are currently working on a solution to extend the feature to all supported MySQL versions, starting from 5.6, and we will have it released as soon as possible.
Please note that MariaDB (all versions) are affected by this as well.
Until then, if your site is using an older version of MySQL or you are not sure about it, please do the following: