Ugothacked posted his 6-4 over at the forums. So the grid is complete.
Which I think is a pretty awesome achievement considering Ragee only open the thread about 5 days ago.
Progress Grid (finished levels in grey, blue in progress)
1-1, 1-2, 1-3, 1-4
2-1, 2-2, 2-3, 2-4
3-1, 3-2, 3-3, 3-4
4-1...