Well, on the mission where you kill the vampire hunter, then have to run out to the boat before the timer goes to 0, I allways crash to desktop, I have reinstalled, tried different saves. Etc etc.
Yep. Just open the game in run in the start menu and type -console when you start it. Then when you've finished the mission and are standing at the boat, you open the console with the §½-button and type SaveJohansen() and press submit. After that you type changelevel2 la_hub_1 taxi_landmark and press submit again. If you're a nosferatu you have to type something different but as mortiz said the post of how you do it is in this very forum.
la_hub_1 taxi_landmark didnt work quite right for me. I was stuck for some reason when the level loaded; couldent move, shoot, but could still use Diciplines, and noclip wouldent let me move either.
I had to changelevel2 la_ventruetower_1 for it to work.