Type these at the password screen:

Password - Effect

UANWIPNA - Level 3 Stage 1
UAGWIPNE - Level 3 Stage 2
UAGWGVNA - Level 3 Stage 3
VANWIENE - Level 3 Stage 4
MUVWLOPT - Level 3 Stage 5
UKRLPHKV - Level 3 Stage 6
UAGWGENA - Level 3 Stage 7
UANWIPNZ - Level 3 Stage 8
UANWQQPA - Level 4 Stage 1
MUBWNNEC - Level 4 Stage 2
UKRLNLHT - Level 4 Stage 3
UANWQIPE - Level 4 Stage 4
UANWQSPA - Level 4 Stage 5
UAGWQSPE - Level 4 Stage 6
MUBWNLZT - Level 4 Stage 7
UKCLNNHL - Level 4 Stage 8