[Display(Name = "Naam", ResourceType = typeof(Resources.Resources))]
[StringLength(200, ErrorMessageResourceName = "Naam_StringLength", ErrorMessageResourceType = typeof(Resources.Resources))]
public System.String Naam { get; set; }

Just create 1 new project for your resourcefiles.

I have it working ...

the only problem i have is when i don't find my word in my resourcefile i get an error.

Currently i am looking for a way to resolve this problem.

(you can follow this thread)

this is a good article