how to add a REPORT file to RESX resource file

You don't need anything like that. The functionality is based on auto-generated code; and it make development much less error-prone: no misspelled resource names, no unsafe casts, in almost all cases.

Let's start with images. You can add an image and edit it in Visual Studio, but I won't recommend that. Consider you created some image file, such as "Picture.png". Create an resx node in Visual Studio and use "Add existing file" to add your file. The file will be 1) added to your project (attention! it will also copy your file to the project directory according to location of your resx file, so make sure no duplicate is created; for this purpose, don't add it manually); 2) the property "Copy" of the file node is made "No copy", because this file should not be copied to the output directory but embedded in your assembly executable module; 3) add a reference to the file to the resource; 3) modifies auto-generated code file shown as a child node of your resx node in Solution Explorer.

Open this file. You will find some static property with the name close to the name of your file, in this case, "Image Picture". It's type will be Image. Just use this property immediately in your code.

With some unknown file types, such as *.rdlc, the situation is a bit more complex. If the file is "not known to Visual Studio", the property type will be raw data, byte[]. It's your responsibility to deserialize it. But you don't need to use resource streams. In cases where you really need a stream, it's simper and safer to use MemoryStream, because memory is filled when you just read the property.

—SA