Fiona,
We use Advanced uploading to provide .doc files to students/parents reporting on progress. Students with a normal role view/download these files with ease. The trick is that the teacher has to put some text in the text box. If there's no text, the file is not visible to the student.
Note: Frustratingly, if the Teacher performs the upload and text in the textbox sequence in the wrong order, the text in the textbox disappears.