How to assign different background images for different 3d views? I was following this tutorial about creating a spaceship in Blender:

As advised I created 3 background images for the three views to be uploaded via the properties bar (N). I did not fail to switch to the ortho mode with the NumPad 5, so that is settled.

After importing the three pictures there is a problem: I assign for example the top view background picture to the top view, NumPad 7 and it is visible. As soon as I assign, say the front picture to the front view and I switch back to the top view, the picture cannot be seen there any more. I have been trying all around for hours and I always end up with the only the last assigned background picture visible and the others then "gone".
I run blender 2.76 in portable mode.
Anybody any idea?

Sorry for the bad link, I forgot to set the filefolder to visible to others except me... Since my status does not allow to upload more than the 15 screenshots here is the correct link  

I think I managed to generate a .blend with the images stacked. The link to upload it in MrZak's post did not work though. I am posting an alternative for the download.

I have read through your advised literature. The load UI was not unchecked.

Meanwhile I have noticed that whenever I try to save the project in the .blend, only the last uploaded picture/blueprint remains, even with the image packed. This means that when I open it, only the last picture remains.

Again sorry for any inconvenience with my virtually poor formatting skills and I much appreciate your efforts.
I have attached a file with 3 views. Try hitting Num 7 , Num 1 and Num 3 to view the different elevation views. Everytime you add an image to the background you will have to click on the "Add image" button. I believe that may be the reason why you could not get more than one image to show up on your viewport.





Alternative Methods

However there is a better way of working with image plane. Using import image
as plane. Here you get a polygon created to match the aspect ratio of your image and the image is applied as a shadeless material. This gives you more control in positioning your image planes and make them visible in all views including the 
perspective views.

Note : You may also want to turn on lock transformation for the planes.



Here is the download for the alternative method.