The game works perfectly fine in single player mode!
What does not
The launcher eu3.exe (use eu3game.exe instead)
What was not tested
I recommend you install PlayOnLinux as it is a nice wine frontend and makes it easier to carry the steps to get the game working nicely.
You can find the modified .txt and .reg files and the needed .dll here:
Let me make one thing clear. Older versions of wine needed a lot more fiddling and tweaking to get EU3 working but this is no longer the case. Just follow the steps here on a clean wine 1.1.36 installation.
First run the installers:
Install EU3 first, do not install dotnet when asked
then Napoleon Ambition expansion
then In Nomine expansion
then In Nomine patch 3.2 (may be this step is not required)
finally Heir to the throne
2) Copy d3dxof.dll to your wine windows/system32 directory
3) Run winecfg and set library overwrite
d3dxof = native
and set MaxShadowSize to 0 in the registry key HKEY_CURRENT_USER\Software\Wine\DirectSound
run regedit and import d3dxof.reg and maxshadow.reg (contained i
4) overwrite the files terrain_2_0.fx and borders_2_0.fx in:
your Europa\ Universalis\ III/gfx/FX/
edit the same files and
replace the lines that start with:
float4 TerraIncognita =
float4 TerraIncognita = float4(0,0,0,0);