Is Camera Baking misbehaving?

[Synthercat]

I am busting my head here :

TEST.blend

(6.91 MiB) Downloaded 143 times

How can I project the small cubes into the baking camera?
I use 2 UV maps, one for material and another for the baking
The problem is that while baking I get the huge squares map not the small like I have set it up with the other UV. How can I scale the UV map as I want???
I can't seem to set it up or it seems that it does not work

Here is the file to play around :

TEST.blend

(6.91 MiB) Downloaded 143 times

Also The baking camera only works with one of the 2 UVs (it give a black image on the other) why???