Korean Font is Broken!!

Hi, someone may know that our korean D&D miniature members are playing EC (named KEC) in vassal. vassal and this module was great. But recently we got some font problem.

Our korean member usually use korean font (korean language), and it was ok. But with 2.6.4 version, we can't see other's chatting collectly. (about half of them is right, but other's are broken like a rectangular).

So please, can we get any help for fix this problem.?

Thank you