Just thought I'd post this for anyone looking to hang a Ray2. I wanted to build a lighting scaffold for my two Ray2s and color LED bar. The most useful information I can offer is that while trying to think of a way to attach them to chain, I happened to find (in my box of misc screws and hardware) various sizes of eye screws; one of which fit PERFECTLY into the tracks that the stock attachment device plugs into. Not having the box they originally came in, I can't say what size or product # they are but if so inclined I'm sure the correct ones can be found at most hardware stores. They fit perfectly; snug but not tight; remove them and you can't tell they were ever there.
For my scaffolding, I used 90' angle aluminum (1/16" x 1/2") for the sides and front, with Flat (1/8" x 1/2") for the support beams. Used some crap 12lb chain they had at the hardware store, wasn't much to choose from. Fortunately the entire structure with lights is still very light. I might change it if I find something better. All fastened with aluminum pop-rivets.
The 2 side bars attach to the wall via 2 steel angle supports with 1 screw hole on each angle (2 total), which hang on 2 eye screws bent open into "hooks". This arrangement allows me to shorten the chains thus lifting the entire front of the scaffold into the air for working in the tank, as it only sits about 2.5" off the surface of the water. In this raised position, the lights still point straight down as they hang from chains attached to single point on each side from the scaffold.
It doesn't look like it, but it literally took me all day, but I am pretty anal about getting everything nice and, of course, every little tiny miniscule problem that could have occurred happened at least once. That's just my luck though...