If you haven't built that system yet, check out my grow, it is basically the same thing without the hassle of a floating platform.

A couple critiques if I may:

Hang your lights about 2 inches from you plant and keep it that way. The first plant me and my buddy grew we just stuck a light way above it and it turned out really stringy. My new setup I keep the lights almost touching and I have bushes!

I don't know what light you have exactly, but I've tried a few CFL's and the ones the plants like the most (clearly all lean towards the same ones) are from HD and were about $7. They are "100w" CFLs made by invision (? the brand is something like that). It is a very "white" light and is supposed to be like daylight. Every other bulb I have tried next to them seem more yellow.

Use FF nutes. They rule.

Don't line your grow cab with black. Black absorbs light. Your best bet is a High Gloss White. Krylon makes some great spray paints for this, but make sure you properly air out the cabinet (trust me fumes kill). The best thing you can use is mylar, obviously.

Looks good so far though. Good luck and feel free to check out my post:
My First Grow: Soil, DWC, & Aeroponics

-Solo-Man-