Thanks for your findings, I'll take a look once I've time for this, need to finish some other things first.
I also think you can add multiple fallbacks to one font
You're right, in Windows these are the default CJK fonts:
Meiryo ( was the default in XP/Vista )
If you take a look at the Windows registry it looks like this:
Fallbacks for Segoe UI:
MSGOTHIC.TTC,MS UI Gothic
MSJH.TTC,Microsoft JhengHei UI,128,96
MSJH.TTC,Microsoft JhengHei UI
MSYH.TTC,Microsoft YaHei UI,128,96
MSYH.TTC,Microsoft YaHei UI
YUGOTHM.TTC,Yu Gothic UI,128,96
YUGOTHM.TTC,Yu Gothic UI
SEGUISYM.TTF,Segoe UI Symbol
Fallbacks for the default CJK fonts:
So you will just need to add it to your registry and I guess it should work the same.
If you take a look at this here, there are the listed Wine CJK font fallbacks for the default Windows CJK fonts.
I would personally first manually install the CJK fallback fonts in the right font directory and add/import the fallback links
( for the fonts you're using in the theme ) to the Wine registry. And then run sudo fc-cache -f -v to clear the font cache.
P.S: You can also install only the CJK fonts via winetricks ( I don't think you need to install allfonts ), there is also a lot of stuff
if you search "wine cjk fonts" or "winetricks cjk fonts" in Google.
P.P.S: I saw in your first screenshot that you did not change the DPI in Wine via registry or Winecfg, that is why you have such small
context menus. Take a look at this here or via registry.