Go to Settings (the cogs icon in the top left hand corner) and locate the bar where your current score is displayed. A prompt will appear, asking you whether to confirm the resetting of scores. Press ‘Yes’ to confirm or ‘No’ to cancel.
The default help language is English, but this can be changed to one of over 100 languages. On Settings, there is a bar with three flags and ‘English’ - press this and a list of languages will appear. Simply select your native language and the app will be automatically updated.
On Settings, you can change the volume by dragging the bar towards the right to increase the volume and towards the left to lower it.