Portal: Prelude Forum

In version 1.1.5, I survived the first GlaDOS encounter and got the portal gun which can only create blue portals.  Then, I spent a long time looking for the way to enable the gun to create orange portals.  During this process, I rode the elevator up and down between GlaDOS' level and the main Aperture office level at least one extra time (beyond what is necessary, and beyond what most players likely do).

I finally got the orange portal gun, and then I got the Morality Core.  However, when I tried to take the morality core to GlaDOS, I found that the elevator had vanished!  Only an empty space was where the elevator should be.  I could see the elevator shaft going upward, but no surface of the shaft would accept a portal, so I couldn't climb it that way.

I used a video walkthrough to determine that the elevator is not supposed to vanish.  I re-loaded the game from an old save (from just after I survived the GlaDOS fight, before I rode the elevator) and re-played the game from that point, using the elevator only the normal number of times.

This time, when I got the Morality Core and returned to the elevator, it was there.  I was able to use it to take the Morality Core to GlaDOS and finish the game.

Therefore, I think version 1.1.5 has a bug relating to the elevator.  The elevator can disappear, especially if you use the elevator more than necessary.  This bug makes it impossible to finish the game.  Your only option is to re-load from an old save, if you have a save which is old enough.

I hope this bug report is helpful to you.