From the Dudley Knox Library:
Upgrading to OS X 10.9 Mavericks may disable Java or remove it. If you have installed OS X 10.9 Mavericks, you will need to make sure the prerequisites are installed to ensure WNC 4 functions correctly on the computer.
If you are prompted to download Java when attempting to install Write-N-Cite 4 for Mac after upgrading to OS X 10.9, please restart the computer and download Java by navigating to the Apple Icon > System Updates.
Once you have reinstalled/enabled Java, please check for Microsoft Office updates. You can check for Microsoft Office updates by opening Microsoft Word and navigating to Help > Check for Updates.
Once you have updated Microsoft Office, installed all system updates for OS X 10.9 and have verified that Java is enabled in OS X 10.9 Mavericks, please restart your computer and reinstall the latest version of Write-N-Cite 4 for Mac.
If you need further advice please contact firstname.lastname@example.org giving full details of your problem and also the versions of Java, OS X, Word and WNC4 that you have installed.