If you haven't got the time to play through the game and want to go straight to a particular level on the Medium difficulty setting then these case-sensitive codes are for you. Just enter them at the 'Password' screen to go straight to the desired level.

Unlock Level 1:
Enter the code VDG*GNCJ

Unlock Level 2:
Enter the code VHJYDRY7

Unlock Level 3:
Enter the code Q8ZPSZBN

Unlock Level 4:
Enter the code QK5KN3JH

Unlock Level 5:
Enter the code QG8KQGSB

Unlock Level 6:
Enter the code QK8KTKWF

Unlock Level 7:
Enter the code Q96KHHK7

Unlock Level 8:
Enter the code QJ4KG2HG

Unlock Level 9:
Enter the code VRHYD9VF

Unlock Level 10:
Enter the code VLF4CBMZ

Unlock Level 11:
Enter the code QM7KWWYH

Unlock Level 12:
Enter the code VJSPDJN!

Unlock Level 13:
Enter the code V79*CYWF

Unlock Level 14:
Enter the code QDD*M6Z6

Unlock Level 15:
Enter the code Q17K99*W