After installing this package you must follow next steps to run designer:

1. Install one of these packages to include WorkflowEnginene.NET persistance provider in your application:

WorkflowEngine.NET Provider for MSSQL PM> Install-Package WorkflowEngine.NET-ProviderForMSSQL

WorkflowEngine.NET Provider for MongoDB PM> Install-Package WorkflowEngine.NET-ProviderForMongoDB

WorkflowEngine.NET Provider for RavenDB PM> Install-Package WorkflowEngine.NET-ProviderForRavenDB

2. Initialize WorkflowEnginene.NET runtime in getRuntime property in DesignerController (DesignerController.cs)

Instructions is here: http://workflowenginenet.com/Documentation/Detail/howtoconnect

3. File names in the project may be different from those set from NuGet (!). It is also necessary to check the sequence of initialization of Jquery and JqueryUI. 
In the _Layout.cshtml file, perform re-initialization of the library. Look at http://workflowenginenet.com/Articles/Item/wfe-alternative-wf for instructions.

4. Run your application and open /Designer - page