Getting related entities ASP.NET WebApi OData v4 results in “No HTTP resource was found that matches the request URI”

I followed this asp.net tutorial by Mike Wasson, and managed to set up the related entities just fine, but when I applied this logic to my project the more complex entity relations (in that there are more of them; that’s the only difference) wouldn’t succeed in an OData call, I got a 404 with this payload:

Web Api won’t download file using jQuery Ajax and Basic Auth

I am using the ASP.NET Web API to build a prototype of a web service (and site) which has a method to download a file. When the user on the front-end presses the export button a jQuery ajax GET request is made and received by the controller which on it’s turn calls the method named Excel (shown below). The method runs without any problem and finishes. When I look in Chrome at the header (see https://skydrive.live.com/redir?resid=2D85E5C937AC2BF9!77093) it receives the response with (as far as I am concerned) all the right headers.