I would need to see your shader code in order to determine what the issue could be. I tested the project files again just in case something was wrong with the shader but it worked fine for me. The only thing I can think of is that indeed the dot function or something related to that is not working properly. Also make sure that your shader and the one from the project files has a different name, both the file and also within the shader itself otherwise you might be using the exact same names and not seeing a difference in the files.
