To install the 3ds exporter, do the following:

1. If you have a previous version of the exporter, delete all your previous 
   files and remove any existing toolbars / buttons before installing the new 
   one. 
2. Copy the 'scripts' folder into your 3DSMax folder
3. Copy the IPhysique_3dsmax5.gup (for Max5) or IPhysique_3dsmax6.gup (for
   Max6 and Max7) in the 'plugins' folder to the 'plugins' folder in your
   3DSMax folder.
4. Open your 3DSMAX and run MAXScript. (choose MAXScript/Run Script...)
5. Go to folder 3DSMAX\scripts\orge\macros and run "ogreToolbar.mcr"
6. After you run the "ogreToolbar.mcr" there is nothing appears on screen yet. 
   You just need to go to /Customize/Customize User Interface... 
   Choose Ogre Tools from Category. Under the list there will be 
   (maybe 3 icons) "Ogre Exporter" icon shows up.
7. Create a new tab with the name "Orge Exporter" (or whatever you want) and 
   drag the icon to the tab.
8. That's it. You are able to run the exporter. Everything you need is in that 
   little icon. 

The OGRE Team would like to thank Banania for the latest exporter, and EarthquakeProof for developing the original exporter.