*.efs files involve UTF-8 (Unicode Transformation Format) encoding. If you use built-in editor, your scripts will be encoded to UTF-8.
If you use another editor (Notepad, Wordpad etc.) you should be sure that your scripts are saved with UTF-8. This step guarantees the correct mapping of regional symbols during the script operation.
Thus, if you have some problems with correct mapping of regional symbols, open your script in Notepad (or another editor with UTF-8 encoding support) and save it selecting "UTF-8" in Encoding section.