A lot of concerts here aren't confirmed to quite close to the show, Megadeth was only confirmed about 6 weeks out. There is still 5 months to the possible shows.
That's interesting, I hadn't heard that before. I hope you get to see them. Would restrictions be more relaxed in Hong Kong, do you think?
And if you have trouble with the presale codes, I'm sure some friendly folks on here will help out.