In version 0.4, you can edit the gesture mappings from the preferences panel.
Pictured below is Andy's customizations. He disables all of the up-down gestures and because the middle mouse wheel on the laptop doesn't get recognized by Mozilla, remaps rocker gestures to navigate among the tabs.
Pictured to the right is the top level customization dialogue. From this view, you can inspect the current mappings. At the bottom is shown a delta from the default mappings.
The current supported areas for gestures are Global, Browser, Mail, View Source, and Print Preview.
Editing MappingsPictured below is the dialogue for editing individual mappings, accessed via the "Edit Mappings" button on the right bar.
The top level "Gesture type" menu allows you to assign normal gesture, rocker gesture, and wheel gesture actions to certain functions.
By selecting the function in the first popup, you can make it easier to specify an action. To program a stroke sequence, click recognize beside the text input for the gesture code.