cant remember who it was posted this week saying they had completed it but ive started playing it this week and have got a bit stuck......

im at chapter 15 and i need to get sam through the office level without the guards seeing her?????? she has to retrieve the laptop so i guess i have to get her up to the top.....

but which ever way i try and go i get spotted.....and she is on tip toe.....

any help or tips would be good cos i like the game but this bit has got me scratching my head a bit....................... and there aint much hair left !!