Heres what i am going to be building soon i already build a similar one but with 3 bulbs and it works very well and thats with just white cardboard no mylar in there yet! anyways heres my diagram its pretty much says it all!
Those designs look good but I always wonder - how can you move lights around to position them. With cfls, it is critical to get them in close so moving them, even from day to day, is often necessary.