This sequence sounds a bit fiddly. From the walkthrough:
Go outside and open the cabinet with controls of the recovery crane.
Press the top red button to start the engine.
Press the red button at bottom left to get the 4 stabilizers to hold the truck firmly.
The levers can be clicked on at top and at bottom.
Adjust the arm so that it is a bit diagonal to prevent hitting anything. Use the middle lever - click the top part until it can't move anymore. The crane is diagonal.
Turn it to get the top part facing the roof now. Use left lever to turn. (See picture.)
Now extend the crane to reach the window. Use the right lever.
Adjust the 3 levers until Lara says that it now faces room number 2.
Do you have a place not too far back where you could restore your game and try playing through this again?
Otherwise, MaG probably has a saved game that would get you past this section, if needed.
