Good lookin grow Octagon. Im sad that you had to move them to a PC case, the height limitations are killer. If you HAVE moved them back to a closet, I had some advice for ya. You had mentioned using a piece of wood to block the door but it was a pain. Check out my grow and what I came up with, I used a white roller shade and mounted it on the inside of the door.
It blocks light VERY well and its white so it reflects. Its also very cool to pull the shade up to enter the room, feels like im in a science lab or something haha.
The link for my grow should be in my signature, i just started less than a week ago but the shade was only $11.97 at walmart and there are a couple pics if youre interested.
Good luck Ill stay tuned
KB
EDIT: oops I must have forgotten to read a page, I see that it is back in your closet. Having heat issues with those small lights eh? You using any fans? I find that keeping an oscillating fan in my closet keeps my temp around 75F/24C quite easily, and I have 5 lights currently. My closet space may also be a bit bigger but if you are really up for gettin your hands dirty you could cut a hole in the wall and vent it out under your house. Patching a wall back up is really quite easy when its time to move, thats my plan if things get too hot.