Selection criteria is a worry. Again I do not know for sure but have heard that New Zealand will only have 5 places allocated this year. We sent 38 to Terrigal (much closer than Halifax but still an indication of the demand from here). We may be a small country but we have many sailors. In the latest Olympic class rankings there are three kiwis in the top ten for Laser. No other country has more than one. So for a mid fleeter like me to gain a place at the Worlds would be difficult in the extreme. Likewise any selection races for NZ will be in the North Island and therefore expensive for southerners to get to.
For the Master Worlds it has to be much higher since there will be something like twice the number of boats sailing (or more) with many fewer countries participating.