Boolean Modifier in 2.74v

another challenge: Trying to create a shape outlined from the background picture. I start with the plane and them extruding and editing vertices until I got the shape right. Then I extruded to get the desired thickness of the model. Now I have to create two holes in the object, different sizes. I add a cylinder, size it and place it where the first hole is supposed to be, duplicate it, resize the duplicate and fit it to second spot. I size them so they are longer than the object on both sides. Now I go to modifier and choose boolean modifier. No matter what I do in it (with plane selected or cylinders) and every possible option chosen, it just doesn't work. Period.
Am I doing something wrong or it's a glitch/bug within this version of Blender (2.74)?

Every help will be more than appreciated!

Good morning,
Have you had success with Boolean modifier using basic shapes? You will probably need to post pictures or an example of you models since your set up mesh sounds possibly complex.
Good luck.
Scooter

I actually tried it with basic shapes too (adding cylinder to a cube - trying to make a hole in a cube) but didn't work. I noticed when I clicked on boolean modifier and it appeared on the right, the name "boolean" was in orange. does that make any difference? I watched tutorials, have a book on blender 2.7 and they all show how it's done, and I followed the same process, and it just doesnt work. Could reinstalling Blender help?
I'm just going crazy since it's quite a simple process.

PS. How do I post a picture here?

I do think the "Boolean" changing to orange indicates a problem.

To post an image, click "Host an image" on the tool bar above your listing.
A popup will come up and upload you image using the File browser. After selecting the file, click :"upload"
then, another popup will come up with three options. Select the complete text in "image" and copy it.
Then paste that in your posting.
As you can see, I have had to ask the same question.  Click preview to see if it worked.

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Should try blender booltool (search with google). It is very easy to use and works 100% for me with blender 2.74
here is link:
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