You need “something” to use in the computer. :) Without spoiling it for you too much, check the rooms around you more. Remember to keep flashlight turned on. Some objects don’t show if it’s off. Good luck!
We should provide a full walkthrough soon.
For the signs please click on the area just below the sign, it’s the Save Point. It was a bug we didnt manage to eradicate in time. :p
Oh wait... i just realized... thats a later part. You have the beaker now? Check the room with pits more thoroughly again for a locker. You will get a clue there. Then remember the beaker description reminds you that it can hold liquids. :)