Issue cannot be reproduced at Esri Production Mapping 10.5.1 Patch 3 Build 1437. Apply the latest patch for Esri Production Mapping 10.5.1.
解决办法
Modify the settings from Evaluate Map while exporting from Data view instead. Click OK from the Color Mapping Rule dialog to accept the changes and close the Export Map window without exporting. Switch back to Layout view and Export Map again; the changes persist and still appear when clicking the Map Colors button.