Chinese support in Mockups

Mockups is a cool tool. But it's a pitty to find that Chinese character support is too poor. I choose Use System Fonts in menu, this helps me to type and display Chinese characters in Mockups. However, when I save file with a Chinese name, I can not see the filename in Mockups. For example, I want to link a file in some objects. In link box (that combobox), all Chinese characters are disappeared. Maybe UTF-8 should be used?