To get hard badge:
1) do walkthrogh
2) redo maps using as few blocks as possible
For me, the hardest part was to find out the plausible limits of levels, that could be reached. I found them to be: {{12,20,15}, {21,16,17}, {40,32,38}, {12,23,22}, {10,13,19}, {17,14,26},{16,12,20}, {31,24,16}, {20,29,16}, {18,30,24}, {15,29,20}, {32,29,29}, {27,20,36}, {33,30,18}, {13,31,20}} = 1005 points.
Hope it helps a little.