In the settings window you can choose one of 7 creek themes, which you want the saver to start with. Your choose is changeable at any time. Just click the picture. (To test this here, you have to reload this page after changing a setting.)
While running the saver, you can change the theme by clicking the relevant button. (forward or back ). That does not modify the start settings.
Because you have these options to customize some settings while playing the
saver, you need to quit the saver by pressing a key of the keyboard.
In the settings panel you can adjust the sound by click on the loudspeaker symbols. ("Loud, medium, low and off). These settings work relatively to the basic loudness which you set on your PC. (To test this here, you have to reload this page after changing a setting.)