If you installed Word after you installed Maximizer, you may need to uninstall Maximizer, install Word, then reinstall Maximizer. Alternately, you may just be ableto install Word, then use the "add / remove programs" feature in XP to "Modify" your Maximizer install to detect Word by removing Word support from Maximzier, then re-adding it.
Maximizer Software support for Microsoft Word 2007
Microsoft (Office 2007) Word Integration Setup
-Ryan