Is your main prep area on the island or to the sides of the sink? Is the range in the island and are you using a hood (I assume downdraft given the drawing).

It looks like you have a Lightolier 1129 adjustable reflector trim (see links below). I have experience with Lightlier fixtures, but not this specific model. My hunch is that the weak point is where the trim plugs into the socket cup (see the righthand side of the second page of the IS_1105.pdf below, figures K and L). Lightolier fixtures use a socket cup that clips onto the reflector *and* contains the bulb socket. However, on the adjustable trim (yours), the bulb does not plug directly into the socket cup, but instead plugs into a separate bulb socket which has some leads that plug into the socket cup. My guess is that this might need some retightening (by hand). By the way, you can probably twist and pull the entire fixture out of the ceiling (it's held in by friction clips around the perimeter). The fixture will be somewhat L-shaped, so it won't be a straight-down pull, but will require tilting it at the end. Pulling out probably won't be necessary if it's only a loose connection with the socket cup. ***Here are some good pictures on Ebay showing what the fixture looks like. The fourth picture is particularly good, as it shows the socket that screws into the socket cup. That big hole that the socket wires are coming out of is where the socket cup clips onto the fixture. http://www.ebay.com/itm/Lightolier-1129WH-Recessed-Incandescent-Lytecaster-Light-Reflector-Trim-/151437517101?pt=LH_DefaultDomain_0amp;hash=item234261212d ****Lightlier documentation below: http://www.lightolier.com/MKACatpdfs/1129.PDF http://www.lightolier.com/MKACatinstr/IS_1105.PDF http://www.lightolier.com/products/index.jsp?CATREL_ID=21031&CAT_ID=24316

We had a 4' Sierra Dome on display at out store. DH wouldn't cut into the flat roof, instead he lowered the drop ceiling in an area about 12'x 12'. Put the dome in the center and then put 4' long florescent shop lights upside down in a square around it. He covered all the surfaces with crumpled foil. Over the years he found that aluminum foil would disperse the bounced light nicely. All four shop lights were on a wall switch. I cannot tell you anything about the electrical. Since you didn't describe your structural setup above your skylight, it would be difficult to be specific. The Sierra Dome site has PDF downloads for installing their domes. Perhaps you could adapt the information to your needs. Here is a link that might be useful: Sierra Domes

There are 2 spring loaded arms on the sides to which the cover is to be attached to.