If all you care about is re-mapping Modifier keys, you can do that without Microsoft's software by just going to System Preferences > Keyboard > Modifier Keys... For the eject button, you can use F12, or you can also add an eject button to your menubar (see http://www.methodshop.com/gadgets/tutorials/osx-menuextras/index.shtml). Then you can avoid the keyboard software altogether (which seems to cause many other problems). Not sure if that's what you're looking for.
My G5 recently died, and I upgraded to a MacPro 2 x 2.26 GHz Quad-Core Intel Xeon, and my keyboard is not working correctly. It seems that the Microsoft Intellipoint software does not work right. I don't really care about most of the bells and whistles, but I really need to remap my crt and alt keys to their mac equivalents, and add an eject key. Without those this keyboard is useless, and I need it, as I get bad carpal tunnel syndrome.
Is there alternate software than microsofts that will work? I am willing to buy it, just need to know my best options.