Now think about this,
I reckon that Takua saw a battle between Makuta and Mata-Nui and saw Mata-Nui loose against his brother. So Takua went to group together the Toa stones to bring peace to Mata-Nui.
That's why Takua was seen outside Kini-Nui at the start of the Mata-Nui game and the foot treail of the Toa was new because it would have been withered away by the sand. The seaweed covered the capsule when it landed.
What do you think?