Hi Sahand,
I purchased this CD-ROM off e-bay which I just received in the mail today. I've gone through it and Brad is correct, it is the demo.
It starts off on April 13, 1912. You are in your cabin when you receive a message delivered to you by your steward from Penny Pringle. She asks you to meet her on the Grand Staircase and when you do, you are asked to find a photo of Andrew Conkling. You pay a visit to Eric Burns who is in A-29 and ask him about the photo. He tells you he might have taken it, but he doesn't have time to show you at that moment. After talking about his wife, he asks if you've seen her in which you reply no. He then tells you, that if you do see her she is wearing a black dress and that he will wait for her in the cabin.
You walk back to the Grand Staircase and happen to notice his wife their, so you return to his cabin and notify him where his wife is. You then proceed into his cabin and develop the photographs that are there. You find the photo you are looking for and then walk back to the Grand Staircase to hand it over to Penny. You give her the photo and she says to you that the agents will be pleased with your work. She then tells you that you are ready for your next mission, but you shouldn't meet again until she summons you and then it ends.
The only differences between this CD-ROM and the actual game is that this one features the trailer, and a screensaver with over 100 images from the game. The tour is included, but you don't tour the ship as you do in the full game. It shows you different images of the ship, but you cannot walk around.
Basically, it's an interactive mini-adventure. It's a good CD-ROM and it shows some images not seen in the actual game, but if you decide not to buy it you wouldn't be missing out on a whole lot.
I would have replied to you earlier, but I wanted to wait until I went through it so I could answer your question properly.
I hope this helps.
Best regards,
Jason