No Jar - Bug

[jens]

If you upgraded from 1.0 to 1.0.1 after having loaded the level with the red tissue blocking the path, which you needed to make the acid for, then the tissue goes away due to a save error between 1.0 and 1.0.1. So you will have to replay from before you first loaded that level or check the thread with saved games and take one there close to where you are now.

http://www.frictionalgames.com/forum/thread-4825.html