Spark View Engine Missing Libraries visual studio 2010

Question

I am using the Spark View engine with asp.net mvc3, gotta say I love spark bindings are awesome!

Everything works fine however development is extremely painful at the moment because any time I change any of my code I get Runtime Binder errors such as

The type or namespace name 'RuntimeBinder' does not exist in the namespace 'Microsoft.CSharp'

I am forced to clean and rebuild my solution and restart it and it works fine after that. Well at least until I make another code change and am then forced to do it again. Stopping IIS instance and starting project does not work I have to do full rebuild first.

I am running in Debug.

I have Rebooted,Checked Referenced DLL's, Cleared all files out off Tmp,Checked my web.config and spark file. I have added the following code in my global.asx file as explained here. Spark views work initially, but then get a "Dynamic view compilation failed" error after 30 minutes or so

  private void PreLoadAssemblies()
    {
        // Deal with the compiling issue with Spark.
        var initialAssemblies = AppDomain.CurrentDomain.GetAssemblies();
        var di = new DirectoryInfo(Server.MapPath("~/bin"));
        var files = di.GetFiles("*.dll");
        foreach (var fi in files)
        {
            var found = false; //already loaded? 
            foreach (var asm in initialAssemblies)
            {
                var a = Assembly.ReflectionOnlyLoadFrom(fi.FullName);
                if (asm.FullName == a.FullName)
                    found = true;
            }

            if (!found)
                Assembly.LoadFrom(fi.FullName);
        }
    }

I guess this is not a crucial bug/problem and may not be worthy of stackoverflow users time as I can work around it but its bugging me more and more each day, and maybe someone has fix.