In some situations, the touchscreen loses its calibration. You might touch the mirror in one spot, but the mirror thinks you are touching a different spot. You can fix this by restarting:
Unplug the power cord from the back of the mirror, wait 3 seconds, and plug it back in.
The mirror will restart automatically. In most cases, it will log in automatically. If it doesn't, take the keyboard (note: turn on the keyboard using the switch) and type the password (vintage1 / vintage2 / vintage3). You can find the correct serial number on the sticker on the top/back of the photobooth.
Give it 2 minutes to allow the touch to initialize properly.
On the desktop, start the 'Touchpix' app and make it full screen.
Done!