While it still isn’t possible unfortunately to include other international readers in the Methoxy-7 Challenge, I just talked with Tim and he feels it’s workable to make Canadians eligible for the Methoxy-7 Challenge.
The reason why initially this wasn't the case is that the seizure rate from Canadian Customs is pretty high.
The solution is that Canadians will be accepted with the selection process being "blind" to country of residence, but they are at the risk of not getting the Methoxy-7 if their Customs service seizes it. Hopefully everyone will be lucky and actually get their package.
So that's good news!