VM_OVERLAY_SCROLL X, Y, W, H, COLOR
Scrolls a rectangular area of the overlay window.
- X: X-coordinate of the upper left corner in tiles.
- Y: Y-coordinate of the upper left corner in tiles.
- W: Width of the area in tiles.
- H: Height of the area in tiles.
- COLOR: Color of the empty row of tiles that appear at the bottom of the scroll area.