The CyberViewer preferences window is accessible either through the Cyberviewer menu, or the preferences button in the history window.
 
History List
The first group of controls in the preferences window are for indicating how many entries you want CyberViewer to keep in its history, or how long you want them to remain in the history.
Keep the last n pages - Select this radio button if you want to specify the total number of entries to be saved in the CyberViewer history. Use the popup menu to choose the number of pages you want saved. When the maximum number of entries is reached, the oldest entries are removed as new entries are added.
Keep Pages for n days - This lets you specify how long you want an entry to stay in the history list before it "expires" and is removed. Use the popup to specify the number of days you want an entry saved. Note that if you use this option, there is still a maximum of 400 pages that can be stored before other entries are removed (oldest first) as new entries are added.
Page Loaded Notification
Use the second group of controls to configure CyberViewer to play a sound when a web page is finished loading. If a web page is taking a long time to load, this can be a very handy option, since you can work in other applications, or open other browser windows, and be notified when the page is done, without having to wait around for it or check back periodically.
The first radio buttons apply if Navigator is the current (frontmost) application, the second group of buttons apply if Navigator is running in the background.
Always - CyberViewer will always play a sound when a web page is done loading.
Never - CyberViewer will not play a notification sound.
Only if window is not in front - If Navigator is the front application, then you will be notified of web pages loading only when they load in windows other than the front window.
Play Sound: (popup menu) - this popup is for choosing the sound that will play for notification. The list includes all system beep sounds (the same sounds that can be chosen as an alert sound in the Sound control panel), plus one called "Soft Beep", which I've added because it's distinct, but not as annoying as the other system sounds when you've heard it for the thousandth time.
To add new sounds, you can add alert sounds to your system (either by recording them, copying them to your system file, or any other scheme you may know of), or, if you want to get fancy, you can copy a (named) 'snd ' resource directly into the CyberViewer extension, and they will also show up in the menu. If you do this, be careful, you're on your own.
Duplicate Page Handling
When a page is loaded that already exists in the history list, CyberViewer can do one of three things: it can either add another entry to the top of the history list (resulting in duplicate entries), move the entry to the top of the list (eliminating duplicates) or do nothing (also eliminating duplicates). If you visit the same pages frequently, I suggest you use one of the latter options to keep from cluttering up the history list with duplicates.