PLAY IT HERE: http://www.newgrounds.com/portal/view/
476251

Take the nail from the ground
Go left, pick up letter behind the plant
Use the nail on the picture
Take key
Go right twice, open the janitor's closet with the key
Take the following items: handle, letter and the little part of the mop bur
Go back, then twice left
Use the handle on the window
Use handle
Take letter
Go right three times
Press on the plant's pot
Take key
Go left twice
Use the key on the door
Go downstairs
Take hammer
Go left
Break the vase with the hammer
Take letter
Go right twice
Take the hook on the shelf
Combine hook with the mop's bur
Use the hook on the rope to get the letter
Go back to boss
Enter boss's room

:)

Play the first chapter: http://www.newgrounds.com /portal/view/469538