Content can be snapped to surfaces in the scene using the surface snapping button, which appears on the controller when holding an object close to another object's surface.
While an object is snapped, it can be rotated along the surface by holding the rotation button.
Holding the surface snapping button locks the snapping plane.
Content snapped onto a surface will stay snapped the next time it's picked up, so long as the surface below it is still in position.
Holding the grip button on your dominant hand in empty space enables locomotion controls. A teleport ray appears, and viewpoints become visible as target destinations.
With the grip button held, press the trigger to teleport to the target destination.
Point at a number variable (i.e. RGB color, fog amount, etc.) in Maquette's UI, and it will underline, which means it's selectable with trigger. Select it with the trigger to invoke a numpad for numeric input.