These are some hints and tips for complete the IRON HELIX.
[Beginners Level Game]
Where's DNA?
Garrett - Deck 2 (Hallway), Deck 3 (Front of the elevator door), Deck 4
(Hallway)
Hendryx - Deck 2 (Just outside of the elevator), Deck 6 (Ctrl Room), Deck 1
(Bridge)
Benedetti - Deck 5 (Weapon Ctrl)
Ichikawa - Deck 5 (Just outside of the elevator), Deck 2 (Rest room)
Zyzinski - Deck 1 (Rest room)
Geist - Deck 2 (Aux Eng.), Deck 5 (Main Eng.)
Semenovsky - Deck 4 (Hallway)
Blatman - Deck 6 (Waste)
Ingram - Deck 2 (One of the Crew rooms)
Parish - Deck 1 (Sure, in his room)
Can't find the Video clues?
There are 4 video clues at least. Some of them are useless or meaning same.
Messages are in Deck 1, 2 and 5. Not in hallways.

[For Intermediate Level]
Where is DNA?!
Zyzinski--Deck 2 (Dinning), Deck 1 (Captain's room)
Geist--Deck 1 (1st Officer's room)
Hendrix--Deck 1 (Rest room, Bridge)
Garrett--Deck 3, Deck 6 (Waste)
Ichikawa--Deck 2 (Hallway)
Benedetti--Deck 2 (Bio Lab.)
Semenovsky--Deck 5 (DEEP in the Engineering)
Ingram--Deck 5 (Weapon ctrl)
Captain--Deck 2 (Restriction area)

How to enter the Weapon ctrl room...
Find a weapons specialist's DNA.

How to enter the Restriction area...
Hope you find Lieutenant Commander's DNA.

Where are Video Clues?
Somewhere in the 2nd deck and the 5th (should I say the 7th?) deck.

How to eliminate the Defender...
Let's wait a moment until it comes to the loading deck, and blow
it away.

[For Advanced Level]
Where is DNA?!
Zyzinski--Deck 6 (Waste)
Geist--Deck 4 (near the elevator)
Hendrix--Deck 6 (Waste), Deck 2 (Dinning)
Garrett--Deck 1 (Bridge), Deck 2 (Dinning)
Ichikawa--Deck 1 (Rest room), Deck 6 (near the elevator)
Benedetti--Deck 1 (1st Officer's room)
Semenovsky--Deck 2 (Ladder to the Deck 2)
Ingram--Deck 4 (Restricted area)
Captain--Deck 5 (Weapon ctrl)

Can't find Semenovsky's DNA?
Try to Climb a ladder from the 3rd deck to 2nd deck.

You will find Captain's DNA, but you must keep on
searching for someone's DNA yet.

Can't find Ingram's DNA?
There's a door not shown in the manual.

Where are Video Clues?
Somewhere in the 2nd deck and the 5th deck.

Well, this is enough. Good luck.

Michael in JAPAN