I've got the latest WAB Dev Edition on my local pc. I've created an app that consumes this web map. The web map is fully open/public but only has two layers, which are secured within our on premises AGS using Windows AD authentication.
When I edit the WAB app and or launch it within my local dev env, everything works great. The app comes up, I authenticate against our AD and I get right in and can start editing those layers.
When I deploy the app to our external facing web server, the app hangs upon loading.
I have a second, none editable WAB app deployed on that same web server. It works just fine.
I'm assuming the issue is with those editable/secured layers. I've gotten esri feedback that I need to go the "proxy server" route but that doesn't make sense. I don't want my users to bypass our AD security. I want them to have to authenticate against those AGS layers. There is no AGOL login/named user needed as this map is public. Perhaps I don't understand the concept of the proxy server.