Resolved!
It turns out that when I create the midi of the stems, I always use C2 for comfort.
If I change the OPEN Hat from C2 to C8, in the visualizer it will be higher since they are more "high" notes.
Thanks you! I was able to do it.
Another question, i was able to load multitracks, but for example, the midi tracks: "KICK", "OPEN HAT", and "HAT CLOSED" (Which are drums instruments) appears on the same line.
How do I make the hat can be seen at the top of the preview? I want to separate the instruments and try to make it look good.
Thanks you very much!