Radio Shack Tri Color LED

Hey, so I am making an infinity mirror that fades. I got a Tricolor LED strip from radioshack a while back and decided to try that out. Unfortunately, it wasn't long enough and I had to add 2 segments. Now I have 12 segments. I can get it to fade for the original 10 segments but whenever I try to increase it. The segments I added won't light up. Could someone help me out?

No, sorry. We can't see your project. We can't see what mistake you made.

If you want help you need to provide us with something to go on. A schematic diagram. A close-up well focused picture or two.

Paul