See http://bugs.winehq.org/show_bug.cgi?id=14980
Essentially, to run Office 2007, you have to set an override for riched20. Since Office installs a new, spiffier version of riched20 in its own private directory, and expects to find it there, isn't it a bug that we don't let it have it?
Sounds like it's time to write a conformance test... sure would be nice if that override wasn't needed.