Hello,
This is my first post on this forum...
So, I first have to thank you for all of this, it's a kind of a dream for the arduino debugging process and as an IDE.
In spite of your very patients efforts to explain everything, It took me 2 days to setup VS 2012 correctly.
Registrering, downloading, updating, rebooting and so on was a real pain in the neck and your explanations have been very welcome.

I finally got a localized french version of VS 2012 which makes everything slightly more exotic.
So far, I just spent 2 hours to find the correct property windows referred in this post...
So it seems to be accessible after a right click on the project name and the keyboard shortcut is not F4 but Alt-Enter...
I then can see a "Property window" with the desired "Enable breakpoints" property as described here.
I had to go through the menus "View->Other windows->Property window" to acces to it. 
Note that i translated back to english my french menus.
So here is a link to the screen capture of my VS 2012 french language version.
https://docs.google.com/file/d/0B_g_-ls8xkLmRkdYcXVLdHBSbVU/edit?usp=sharing
I hope this will help some new users like me.
So far, I had not used VS due to its price and apparent complexity.
Again thank you for your debugger, I just have now to make it work and thus save the precious RAM of the arduino.