A method of growing a nitride semiconductor crystal which has very few crystal defects and can be used as a substrate is disclosed. In some implementations this provides a means to use electromagnetic excitation or light-matter interactions to influence, cause, control, modulate, stimulate or change the state or phase of electrical, magnetic, optical or electromagnetic charge, emission, conduction, storage or similar properties. The first and second adjustable mounting tracks are adjustable relative to the ceiling mount such that the space between the ceiling and the support surface as well as the overall length of the side rails may be adjusted by the user according to the intended space. The pallets are delivered to the respective customers. At least one LED is disposed on a first side of the housing and cooperates with the container to emit diffuse or scattered light from the light transmissive portion.