Oh that's nice. I only was able to create some sort of machine gun sound, which was rather simple, but the program seems to have much more potential... given that you know what you're doing.
And I'm not sure why, but for me the scrollbars at the top look like this:
And at first I didn't even realize that there was more to select, until I loaded your sifi-shot example.
Edit: The gray boxes, used to offset the 3 window-buttons in the top right corner, are not the problem I was talking about (btw that solution is quite funny
) - what I meant were these scrollbars right to the three listboxes, used to select the instruments etc. They awake the impression that scrolling down is not possible.