use the spatula

behind the gray block on screen with colour floor squares

sledgehammer

click on left of green tower on screen with drawers. The block is at the top of the left tower

i've got one key left, apart from the other three coloured blocks, and there's this box in the corner with screws on all four corners, but i can't find a screwdriver...

place red block on red square below the shelf to get the handle
SPOILER: (click box to reveal/hide)

1. Click Start and then the down arrow on the next screen (hey, sometimes the obvious needs to be stated)
2. Click just to the lower right of the block to look behind it and pick up the spatula.
3. Click back to the screen with the four coloured squares on the floor and click to the right.
4. Pick up the blue block.
5. Click under the table and pick up the key. Click out of the close-up.
6. Click the bed to turn back the covers and pick up the hammer.
7. Turn right, use the hammer on the yellow block. Click to the left of the big cream block and pick up the red block.
8. Click out of the close-up, put the red block on the red square, and use it to reach the high shelf. Pick up the drawer handle.
9. Click out of the close-up and to the right (picking the red block back up on the way). Click the left of the screen to get a view of the two green pillars. Use the spatula on the left-hand one to get the green block. If you wait on this screen, a hippo will walk across, which you can pick up.
10. Click out of the close-up and click on the drawers. The top doesn't open, the second is empty. Use the handle on the bottom drawer, open it and get the screwdriver.
11. Click out and left twice. Click on the bluish box at the back, use the screwdriver on it and get the yellow block.
12. Click out and left. Put the four blocks on their respective squares. Now I had to click out of the screen and back (say left and then right) for the big grey block to move, but when it does, open the door with the key and you're out.

Like this, like this only the fact that it comes out of the safe room with the notion that where you say direct it was possible. The word, suddenly, polygon was remembered. Nevertheless, as for the toy of the hippopotamus which puts out this noisy sound, it probably is what...

You came out of the safe room (?) with the notion that it was possible directly (i.e. through the door, after you find it). You suddenly remembered the word ploygon? (Probably the cubes). Nevertheless, the noisy toy hippo is probably what...

is under the block that looks like a table.