This error isn't supposed to happen in .55 so I assume you are using a savegame before 0.5. This is a tricky situation I cannot test myself. So maybe the old trick helps:
"Try to reach and open the wardrobe in Alex' room by repeatedly clicking "Ignore" inside the error message."
If this is not helping, you are doomed to
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first, load your save into and try the same trick. It should work there. Then you save the game again in 0.5 and load it into 0.55.
On the other hand, the scene you are stuck is on day 3 of the walkthrough, so restarting from scratch may be more efficient ...