The Office:2001 and Office v.X proofing tools are not compatibe, so copying the OS9 tools to an Office X installation is ineffective.
Office v.X should have installed Proofing Tools into the /Applications/Microsoft Office X/Shared Applications/Proofing Tools folder for you as part of the standard installation. If you did a non-standard (custom) installation, I suggest you remove the Office:2001 Proofing Tools you copied from the Office X folder, then run the Office v.X installer again and install the Office X proofing tools.
(It's possible you will need to run the "Remove Office" tools from the CD's Value Pack/Utiltites folder and re-install Office X from scratch to get that done properly at this point.
You may then choose to run the Value Pack installer from the CD's Value Pack folder and install additional language proofing tools.
If you re-install Office X, don't forget to re-apply the 10.1.2 and 10.1.4 Updaters from
Microsoft's Mac website