Electromagnetic signal delivery for tissue affected by neuronal dysfunction, degradation, damage, andor necrosis, and associated systems and methods are disclosed. The retarding mechanism continuously retards the opening and closing movements of the dipper door by controllably braking or slowing the at least one braking arm using the compressive action of at least one hydraulic piston mounted to the braking assembly. The light beam positioning arrangement includes a light beam generator, such as a laser generator, which directs at least one light beam toward the surface to form a point of light on the surface which provides a visual indication to the user as to the position of the spray container and nozzle relative to the surface.