There is list of some 'advanced'/'hidden' registry settings. Settings which you can not change via the Plus! preference panel in Messenger. This list can be found if you go to the official Plus! website and click on 'help':
http://www.msgpluslive.net/help/registry/
A list of the normal settings, the ones you can change via the preference panel isn't available. But to find out what key to add or change in the default preferences, change something in your own account and compare the changes of your own preference set in registry with what it was before you've changed some option. Most of them speak for their own.
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