Dragging content to the Drum Machine Designer zone creates a software instrument track with a Drum Machine Designer instrument plug-in using the sliced audio content, and a MIDI region to trigger the slices. When multiple items are dragged, each file or region is placed on its own pad in the Drum Machine Designer grid, rather than being sliced and placed on multiple pads.
See Create zones with drag and drop, and PDF
Control Surfaces Support Guide: PDF