The passwords are:
1) operator
2) script
3) patch
4) roses / Go all the way right till you find the secret ammo box.
5) properties
6) lantern /Just complete level 6 with the first pick.
7) faint
8) autopsy
9) aidem
10) lovely
11) log
12) benny
13) before / Go to the north east,there you will find a pink square with an achievement
picture,click it.
14) lolcake
15) knee
16) workspace
17) free
18) slam
19) flat
20) mouse
21) circle
22) logic / Click the Nintendo DS start button to get a medal.
23) ground
24) narrative
25) language
26) 351
27) pinnacle / Nessesary to complete if you want to have all the achievements :/
28) hedgehog
29) yo
30) Click takeover or revive to get that achievement
Seceret area 2) Level 20 Click the cat's/right ear of the mouse
Level 16 Go left till you find a golden cup and click on it
Seceret area 4) sbc
Seceret area 5) Click N/A under the spear on level 30