I use Binsor for configuring Castle and Spark as my default ViewEngine for ASP.NET MVC.  This is how I register and resolve the ViewEngine

container.boo

component "Spark.Web.Mvc.SparkViewFactory", IViewEngine, SparkViewFactory
component "Spark.FileSystem.FileSystemViewFolder", IViewFolder, FileSystemViewFolder

global.asax

container.Install(BinsorScript.FromFile(Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "container.boo")));
ViewEngines.Engines.Add(container.Resolve<IViewEngine>());