CSS fix for the Directory plugin?

1. How to determine the spaces between the different grids.

2. Is it possible to determine the order of the grids.

3. Is it possible to change the disposition of the grid (or at least center them). I actually have 4 grid on the first line and 2 grid on the second line. I would like to have 3 grid on the first line and 3 grid on the second line.