Pro Maps has not been updated to Use MySQLi yet, it is not compatible with MySQLi recordsets.
The Move to MySQLi has to be taken in steps. We First needed to recreate the Built in DW server behavior which are the ground work we have built our extensions on using MySQLi. Now we are working on upgrading our extensions to be MySQLi compliant as well. That is our current project, though I do not have a release date for that will be released.