Tapping on that window will toggle xstroke on/off.
You can change modes by using the mode-change strokes shown below. Some modes may be "locked" by doing the mode-change stroke twice.
Here are the strokes defined within each mode:
[abc] [123] [!@#] [abc - advanced]
[abc] [123] [!@#] [abc - advanced]
[abc] [123] [!@#] [abc - advanced]
[abc] [123] [!@#] [abc - advanced]