I've downloaded and install the x86_64 DEB package on my Debian sid 64 bit laptop. When I launched SoftMaker Office 2018, I noticed many Chinese characters in the menu options appeared to be blocks!
I've tried Chinese input and all is fine.
My system info:
OS: Debian stable-updates sid
Kernel: x86_64 Linux 4.16.0-1-amd64
DE: XFCE
WM: Xfwm4
WM Theme: OSX Improved
GTK Theme: Paper [GTK2]
Icon Theme: Oranchelo
Font: 文泉驿正黑 Medium 10
The Chinese font's name is Wenquanyi. When I set default font to Noto Sans CJK SC Regular, the block disappeared and the charaters were just missing.
Below are the screenshot of the appearance when I used Wenquanyi and Noto Sans CJK as default font.