To stream midi files is tricky. They typically are so small that streaming does not apply. To stream video or any other thing playable with the Real Player, just refer to this type of content in the ram file. If you hit the avi link directly, you ll get the whole nearly five megabytes before the film starts. To stream printable documents, pdf files, they must be optimized for that at creation.
Adobe calls it byte serving .
As I have no Acrobat writer, I can t tell you more about it, but it seems quite straightforward and usual to do. Then put this pfd file on your server and it will work without further ado.