I've put out a new 0.12.3 release that fixes a bug where the viewer breaks loading a flexible layout with a custom initial map view. https://github.com/jumpinjackie/mapguide-react-layout/releases/tag/v0.12.3 - Jackie -- Sent from: http://osgeo-org.1560.x6.nabble.com/MapGuide-Users-f4182607.html