Level 9 Pits ans Doors

[Messanya]

I solved the puzzle with those three teleporters and the riddle underneath that damn pits. But I have no clue how to get these doors open in the room with the pits
please help me

[PSY]

SpoilerShow

1. Behind the iron grate is a floor switch. Drop any item on it. The iron grate will open.
2. Walk through the grate. There's a hidden switch on the wall which freezes the trapdoor. There's another lever at the end of the tunnel. Pull it.
3. Go behind the reappearing teleporter field, walk to the end of the tunnel, and pull the 2nd lever.
4. Main door will open.

PSY

[Messanya]

Thank you very much.

[PSY]

You're welcome