This may be of no help to you, since I didn't use a Diamond light, but I did have the problem you have, and I thought I'd tell you what I did, and how it worked for me.
I put my 9 ft table with the long rail perpendicular to the garage door, and closer to one side wall than to the other, so that the center of the table, lengthwise, was midway between the garage door opener, and the track on that side.
I put a light up near the ceiling, so it didn't hang down low enough to interfere with the garage door when it opened and closed, which I needed to be able to do.
To make sure I had plenty of light with the fixture this far from the table, I used eight 4 foot bulbs. It has worked very well for me, and the compromises I had to make were minimal.
I posted a few pictures of my garage conversion
Here:
The photos didn't focus on the light, but you can see how well it lights up the table and how it's centered between the track and the opener.