I didn't have any problems with my game download and install (in Canada). Sometimes when I've had problems in the past though (with Nexon), I had good luck by deleting (uninstall) the game completely from my PC and doing a "fresh" download and installation. I hope that works for you!
Make sure you have full control on your Dekaron folder (properties>Security>edit permissions)
Then navigate to Dekaron>History or Launcher.config and change 1.2.8 to 1.2.9. Save it, exit and launch again. (I forget which config folder it is, think it's the history one)
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