I've been in Katzenstein's Lab for nearly two hours now. I made it through the entire first part up until where you're trying to get to Grunk, and you have to de-activate all the chimney's. It IS my first run-through, well, full run-through, i've done partial before when I ran out of time. I have like 3 quests that need doing in here, and i'm fed up with spending an extra hour and a half running around trying to activate chimney's. I got the first chimney activated, none of the others will. At first i thought maybe there was an order too it, but i can't activate any of them, or de-activate the one already activated. I'm really upset about this because this is 2 hours of my time down the drain because now I'm going to have to start all over. I am doing this alone, because I know I can, and no friends are online, so it really isn't a quick thing, and i spent a lot of time on it. I'm calling a friend now to come and hopefully activate them for me. A real life friend, but if he doesn't pick up, I'm going to have to start all over.
They don't need to be done in any order. As a matter of fact, on your way to the Lab, hit some of the chimneys as you pass them! I usually hit them all on the way to the book to read about them, and all is already done. It saves a lot of time that way!