One problem with the internet is that from written words it can be hard to detect humor or sarcasm. An answer that is meant as a either a good-natured joke or an insult can easily be misunderstood as incorrect advice, and another answer explaining why a previous answer is an insult can be misread as an insult itself.
Getting to the optical problems: Ho Pei Jiun, I suspect that is one basic aspect of the use of this lens that you are not understanding.
Is your lens in the standard configuration of having the two lens cells screwed into a Copal shutter? Do you know how to operate the shutter? To focus you should move the black triangle so that the shutter blades are open. You should move another level to point to 5.6 so that the aperture blades are fully open.
Here are some simple experiments to see how the lens operates: Take the lens to a room with one window and the lights off so that the room is darker than the outdoors. Hold the lens in one hand with the front facing the window. With the other hand, hold a white card behind the lens. Change the distance between the card and the lens until you see an image of the view through the window on the card. The reason for doing this in a room with dim light and a bright window is so that the room light doesn't overwhelm the light from the lens that makes an image on the card. This is a simple example of the focusing procedure that Jim described in answer to your previous question (www.largeformatphotography.info/lfforum/topic/500885.html). As I explained, the card should end up close to 142 mm behind the back of the Copal shutter.
A second experiment: go to a room without windows and a single light. Hold the lens with the front facing the light and at a distance of one or more meters. Now hold a white card behind the lens and adjust the spacing until you see an image of the light. This time the distance from the white card to the lens will be larger, according to the basic focusing law of optics. You can read about this equation at the Lens Tutorial: http://www.photo.net/learn/optics/lensTutorial.
These experiments should show you how your lens works. Your next step is to replicate this spacing in the camera that you are building, along with some method of adjusting the focus. If you want a fixed focus camera without any means of adjusting the focus, you will need to make accurate measurements of the actual focal length of this lens, which will be slightly different from the design value, and you will also need to know the distance between the principle points or planes. A simple but tedious method of adjusting the focusing is to use spacer shims that you add or remove between the lens and the camera.
Reading some books or showing your setup to an experienced photographer are good ideas. Perhaps you have access to a library with books about optics?
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