A couple of things wrong with this:

  * Your assigned package name (`"Sublime Word Count"`) doesn’t match the directory name in your Main.sublime-menu file. This name is used for the directory into which your package will be installed, so it needs to match what you have in your .sublime-menu file.
  * We try to avoid packages whose names start with ‘Sublime’. It’s redundant, because all Package Control packages are for Sublime Text. I recommend a more descriptive package name like `"LaTeX Word Count"`.