much better controls now
I think that the controls in general and the swimming can be improved by lowering the display resolution within the game or otherwise speeding up the computer (turning off antialiasing and anisotropic filtering will speed things up alot). I overclocked my video card and now the controls are much better. It may also help for the swimming if Controls, Mouse Speed is set to the middle setting...I had mine set at maximum before. For anyone else frustrated at starting this part, you start off by swimming to the first room to the left. Later, you get a chance to practice your swimming. I'm doing the Prague level now...it looks great.