He them puts them back into the computer via floppy disc to change the keys and edit them etc.

The old program he used was Ausiostation by Voyetra but this was the 1995 version running windows 98 (this program wont work on his new PC which has windows xp) and I dont think their current version of audiostation does the same thing.

Basically i need a program that will display a keyboard on screen and will play midi files and enable my friend to change the keyboard keys and manipulate the mifi files. 

I hope someone knows what i mean.

Please help.