Hey man, I have a few suggestions, some insight and some ideas. First off, I use the rapid rooter plugs too. I think that they may be too wet. I find that I get best results rooting clones and seedlings under a humidity dome without the bubbler. Just keep em moist. Moist, not soggy or siting in an inch of water. The water that I do give to them is mixed with "olivia's cloning solution" not to be confused with the rooting gel. This stuff is packed with rooting hormones, speeds up root formation, and wards off molds and other root rotting things. Once they have developed a healthy root structure, move em on in to the bub.
The one seedling looks stretchy. How far away are the CFL's? Flouro's can be hung very close to the plant because it produces such little heat. In fact, your plant tips could be touching the bulb for days with little or no effect.
If you put a fan semi close to the plant so that it's always dancin' it will help to strengthen that long stem.
If you have any other questions let me know.
Peace.