Adding Razor Support

RAZOR: Earlier this year, Microsoft made ASP.NET MVC, Web API, and Razor open source, and this source is now also used by mono. However, since we are using the .NET4 implementation, we still need the original MS dlls. Make sure the following dlls are in the bin folder of .../umbraco/presentation/bin (and in the bin folder of the binary app distro)
External: System.Web.Razor.dll, System.Web.WebPages.dll, System.Web.WebPages.Razor.dll, Microsoft.Web.Helpers.dll .NET 4 versions Umbraco: From the folder, umbraco.MacroEngines.dll (mono develop will not set a refernce to this to avoid circular references, so you can copy it manually or add a post build step)

Note: If you do not have the 4 external, and umbraco macro dll's in the bin folder, you will get a variety of errors:
No umbraco.MacroEngines.dll - language selection is create script dialog is empty
No Syste.Web.Razor, System.Web.WebPages, Sysem.Web.WebPages.Razor - error language extension file is not recognised
No Microsoft.Web.Helpers - File build failed message (due to CS0234: The type or namespace name `Web' does not exist in the namespace `Microsoft'), this error will only report after applying the 'MoveNext' fix below.

Adding Razor to Scripting:
To .../umbraco/presentation/config/umbracoSettings.config,
after the developer section, add

    <scripting>
        <razor>
            <!-- razor DynamicNode typecasting detects XML and returns DynamicXml - Root elements that won't convert to DynamicXml -->
            <notDynamicXmlDocumentElements>
                <element>p</element>
                <element>div</element>
                <element>ul</element>
                <element>span</element>
            </notDynamicXmlDocumentElements>
            <dataTypeModelStaticMappings>
                <!--
            <mapping dataTypeGuid="00000000-0000-0000-0000-000000000000">Fully.Qualified.Type.Name.For.ModelBinder,Assembly.Name.Excluding.Dot.Dll</mapping>
            <mapping documentTypeAlias="textPage" nodeTypeAlias="propertyAlias">Fully.Qualified.Type.Name.For.ModelBinder,Assembly.Name.Excluding.Dot.Dll</mapping>
            <mapping dataTypeGuid="00000000-0000-0000-0000-000000000000" documentTypeAlias="textPage" nodeTypeAlias="propertyAlias">Fully.Qualified.Type.Name.For.ModelBinder,Assembly.Name.Excluding.Dot.Dll</mapping>
            <mapping dataTypeGuid="00000000-0000-0000-0000-000000000000" documentTypeAlias="textPage">Fully.Qualified.Type.Name.For.ModelBinder,Assembly.Name.Excluding.Dot.Dll</mapping>
            <mapping dataTypeGuid="00000000-0000-0000-0000-000000000000" nodeTypeAlias="propertyAlias">Fully.Qualified.Type.Name.For.ModelBinder,Assembly.Name.Excluding.Dot.Dll</mapping>
            <mapping nodeTypeAlias="propertyAlias">Fully.Qualified.Type.Name.For.ModelBinder,Assembly.Name.Excluding.Dot.Dll</mapping>
            -->
            </dataTypeModelStaticMappings>
        </razor>
    </scripting>

This is enough to get you to create Razor scripts. Making them run, however, requires more work