Problem of the start and corners.

[popowi]

It happens that when you start the corners and makes me fatter, along the walls makes me the finest in the photos you've modified the flow attached, are 0.8, 1 and 1.3.
Somebody tell me what the problem and the solution will be gap? or depth, both are 07 and 1.7 respectively.
The measures of the piece are 20x20x10 and the inner lips 2mm

This is flow to 1 and 1.3, they are located equal and failure is beginning at the left edge of the piece.

I have observed that interieors should be 16mm, but if I take me or does flow but makes thinner walls and if wl flow is high have less interior.

little flow
and more flow

configuration

Thanks.