Here is how you do what you are trying to do:
- Use Songverter to convert the KMA file to either BIN or MP3+G. Do not delete the original.
- Use the converted file in Keyrite to take it down 7 as you did before. When you save it make sure you change the title to have something to identify it as modified.
- Import the file into Hoster. I would add it to a Custom Assembly to keep it separate from the original.
You can request in New Features under Hoster for the Key Change to be Extended, but as you say changing a song that far is really pushing it in quality even for an electronic key changer. However they make take another look at it if you request it.