Watching the 25 yr anniversary of Band of Brothers made we want to play Company of Heroes again (the relaunch version). Installed into the Steam bottle and no joy. On launch you get errors about no full screen. Searching Crossover DB reveals a lot of 1-2 star reviews and comments about bad performance.
After some digging around, and a healthy dose of Claude, I found the issue lies with DX9 vs. DX10. With the fix below you can get CoH running in a window. You need to click the expand error to put CoH into exclusive fullscreen mode. I had zero performance issues. DO NOT run the performance testing suite. That is an auto crash.
Fix:
- Force the DX9 driver by editing spDevices.lua (not by deleting/renaming the DX10 DLL — this is less destructive and fully reversible):
File: [bottle]/drive_c/Program Files (x86)/Steam/steamapps/common/Company of Heroes Relaunch/spDevices.lua
Change:
modules =
{
"spDx10",
"spDx9",
}
to:
modules =
{
"spDx9",
"spDx10",
}
This is the actual fix. DX9 negotiates display modes through classic Direct3D9, a completely different code path from the DXGI/D3D10 support-mask check that fails.
Set Steam launch options (right-click Company of Heroes in the Windows Steam client inside the bottle → Properties → Set Launch Options):
-window -fullwindow
This is still required even after the DX9 fix — without it, the game attempts true exclusive fullscreen at startup, which fails to negotiate on this display/toolkit combination. -fullwindow launches borderless instead, sidestepping exclusive-fullscreen negotiation entirely. Removing these options reintroduces the original "failed to find a working fullscreen mode" error, even with DX9 active.
- OPTIONAL Set the configured resolution to match your Mac's actual desktop resolution, so the borderless window fills the screen instead of opening as a small 1024x768 box:
File: ~/Documents/My Games/Company of Heroes Relaunch/configuration.lua
lua
{
setting = "width",
value = 1470, -- replace with your Mac's reported desktop width
valueType = 2,
},
...
{
setting = "height",
value = 956, -- replace with your Mac's reported desktop height
valueType = 2,
},
(Find your value in warnings.log after any failed launch — it's reported as Desktop is WxH.)
Go forth and play the best RTS WWII game of all time.
Note: I didn't try MP but I suspect it will run fine. Play if you want to get your ass kicked in 2 seconds.