OS: Windows 7 SP1
Problem: Displaying a square instead of the word.
This is a bug. I have an old document that I have been maintaining and updating since OpenOffice 2.4.0. It is called Sun Tze War Stratagem 《孙子兵法》. It contains a word (𦮼：艹+己+心), which must be displayed using supporting font like 海峰中日韩汉字超大字符集（SuperCJK）, 方正宋体S-超大字符集, Hanazno 花园明朝. And to input this word, you can use 逍遥笔v6.5 免费版 or 华宇拼音输入法. OpenOffice gave me the same problem when I upgraded to version 3.1.x. I lodged a report and the problem was fixed at version 3.2.x. I tried LibreOffice 3.5.x, the word displays correctly, but when I tried the latest version 4.1.2, it gave me the same problem, a square instead of the word. I tried changing its font to other supporting fonts but none worked, and all these supporting fonts works with other word processors like WPS Office, MS Office, even OpenOffice. I lodged a bug report yesterday and asked to rectify. You can try OpenOffice 4.0.1, the latest version. It should display the word correctly as long as you have the supporting font installed. I personally tried and proved it.
If anyone knew of any workaround to allow the use of LibreOffice Writer 4.1.2 to handle 中日韩超大字符集 correctly, please post and let everyone know.
PS: CJK ideographs in Unicode (http://en.wikipedia.org/wiki/Template:CJK_ideographs_in_Unicode)