Okay, here's the deal: My DS lite's bottom (touch) screen has a large dark "blob" on it where the pixels are darker and the colors are not very pronounced, and it also is flickering. I think I messed up something when I opened it up to clean the L and R button contacts, which were sticking. I've read that there's a "tuning screw" to alter the refresh rate, but I don't know which one it is. I've been googling as much information as possible, but I keep getting overwhelmed with garbage. If somebody could please give me hint of what to do next, I'd really appreciate it. Thanks!