I have noticed that some of the free packs that Yamaha provides for his S series and in mine case the S-670 will not install the file.
The solution to that problem is simple..
1.Open the YEM program on your computer.
2.Load your instrument info file first in to the program.
3.Then open the pack that will not install.
4.Make sure you have the not loading/installing pack in a seperate folder on your USB device when opening it in the YEM software.
5.Then click on the Save as Pack Install file button.
6.After making the Install file you will see that the pack will load on your S keyboard.
Because I have the lowest machine in the X70 series sometimes things will not be loaded and can not be used but it happend with 1 pack so far.
The reason is maybe that some free packs are made for more types of keyboards and that's the reason the .ppi file is missing.
But with a little work with the YEM software you can use the pack now.
Another thing that I want to mention is that you have to delete other packs that you have opened before when you load the new one in the YEM software.
Regards,
Lisa