To answer your earlier question, epoch 57: the app autosaves data every 5 minutes. I will probably take that message out, right now it is there for debug purposes.

There are no vibration customization in place right now. It is limited to 2 vibrations at 3 seconds apart.
The audio button in the middle should bring up an audio picker. If it doesn't , you can still select custom audio by opening the reminder screen > info > the reload button in top left.