well... I'm not Korean but maybe this would help.. why not try to go to the list of this category where you posted this one which is "Foreign Games"... there you can see a thread entitled as The Ultimate Korean Language for Dummies Guide... it was on Sticky so you can easily find it...
hahaha.. I just opened the link you provided.. and.. dem... that's pretty hard if you gonna follow what I've suggested...
so here's my another suggestion why not look for another fishing game which is translated to English? in that way you can never have a problem with registering and even in playing the game....