A detailed case study on integrating a third-party DAM (Wedia) into Optimizely CMS 12 without official documentation. The author walks through the full research process — decompiling the CMP NuGet package, studying CMS.zip internals, and using Geta's Categories package as a blueprint. The solution involves four key patterns: configuring module.config for Dojo, extending ContentReferenceEditor (not replacing it) with a custom Dojo widget, using postMessage to bridge the DAM iframe picker with the CMS field editor, and creating proxy content items (WediaImage/WediaVideo) via a REST endpoint so picked assets become native CMS ContentReferences. A custom Assets pane tab with 'For All Sites' and 'For This Site' roots completes the integration, enabling editors to browse and reuse DAM assets like native media. Code samples are provided for all major components including C# descriptors, Dojo JavaScript, and the proxy content API controller.
