Sounds like the client computer is having trouble with a font suitcase. Either a duplicate font suitcase or a corrupted font suitcase. If so, switching to a different font as a test should cause the data to properly appear on the layout.
There are ways to fix the font suit case issue, but as I am not a Mac user, I don't recall the precise steps for fixing this.
That was it, a duplicate system font! I always forget about fonts! Thanks a ton!