Hi jlim13,
For every mission we have terms and conditions attached to the announcement blog. For instance, December mission is open to US, Canada, UK, and Germany. As for the drawings, every mission might have different rules.
In terms of future plans for those not located in these countries, we cannot make any promises, but we do try our best to involve as many thwack members as possible.
I hope this answered your questions. Happy holidays to you too!