Yeah, just look at where Soth is at first, and then after you take him out just run like hell straight to where he was standing. It will go to a cut-scene automatically.
Use the shadows to strike swiftly and silently, and only do otherwise if compromised...
Still working on it, huh? There are a couple of lights which may help to keep you from getting seen but be careful not to be noticed- once you are spotted, the time starts. I like to use a sticky shocker on the guard out by himself on the catwalk (don't forget to kill him before you get to the ND-133). Even if you are not spotted, the timer will still start when you go up the last ladder so be ready to take out Soth and the other guard.
No I haven't completed it I haven't played it since September thank you. Play the first Splinter Cell Stealth Action redefined and you will find the (sam fisher's voice: Goody its in the thrid section after he takes the elevator to find the SK-20) I'm waiting for ConViction for PC and I hope I can play it on PC. I have Windows Vista Home Premium. Anyone know the requirements of the game for PC?