Deployment issues with Beta 8 application to IIS 10

I'm struggling to get the deployment working for VS 2015 for ASP.NET 5 Beta 8 application:

1. I've installed the httpPlatformHandler on IIS as is needed.
2. I've followed the Publishing to IIS tutorial. 
3. Separate site called (on port 8089), resolving to the wwwroot folder of the published application.

I keep getting an HTTP Error 502.3 - Bad Gateway error in my browser when navigating tolocalhost:8089. 

Does anyone have any ideas?