You can slice samples by clicking and dragging on a waveform, which will cause the selected part of the waveform to be played whenever the pad is triggered.

Tried that out, it works well, but also revealed another limitation—it seems as if I can only trigger two pads concurrently. That may be less a flaw in your app and more an inherent reality resulting from the fact that my keyboard wasn't necessarily meant to be used as a drum pad.

Edit: Potential workaround would be pad-linking (hard kick and deep kick, snare and clap, kick and closed hh if I know I'm playing 16th note hats, etc), if indeed there's no issue with playback of multiple samples and it's only a limitation of the input device.

When I mentioned slicing, I meant more along the lines of setting multiple slice points and assigning the slices to several pads, as one would when loading a drum break into an MPC, for instance. A copy function would accomplish largely the same thing.

Anyway, it's all academic, there's a Maschine sitting right next to the keyboard on my desk, it's not as if I'm actually going to use this as an MPC replacement. Just throwing ideas out there.

Great job though.