Ok, clue 3 makes no sense to me. I can interpret it at least 3 different ways. Help? Do we end up with:
1. 20 pairs of 2.5x6.5 strips
2. 20 different 2.5x6.5 strips (because the greys are different in each)
3. 40 pairs of 2.5x6.5 strips (match the 6 square with *both* sets of half-square triangles that used the dark.
ARGH!