How to install Windows Media Player 11 to a Proton prefix

instructions.md

1. Download Windows Media Player 11, 64 bit (wmp11-windowsxp-x64-enu.exe):

   $ cd /tmp/
   $ curl -O https://web.archive.org/web/20190512112704/https://download.microsoft.com/download/3/0/8/3080C52C-2517-43DE-BDB4-B7EAFD88F084/wmp11-windowsxp-x64-enu.exe

2. Extract the archive:

   $ cabextract wmp11-windowsxp-x64-enu.exe -d wmp11

3. Run and close the game through Steam. A Proton prefix is created on the first run.
4. Go to the game's folder inside Steam's compatdata folder:

   $ cd $HOME/.local/share/Steam/steamapps/compatdata/287290

5. Set prefix to Windows XP:

   $ WINEPREFIX=$PWD/pfx wine winecfg

   Chose "Windows XP" in the drop-down menu and click "OK"
6. Install Windows Media Player:

   $ WINEPREFIX=$PWD/pfx wine /tmp/wmp11/wmfdist11-64.exe
   Press Ctrl+C when the installer has finished
   $ WINEPREFIX=$PWD/pfx wine wineboot
   $ WINEPREFIX=$PWD/pfx wine /tmp/wmp11/wmp11-64.exe
   Press Ctrl+C when the installer has finished
   $ WINEPREFIX=$PWD/pfx wine wineboot

7. Set prefix back to Windows 7:

   $ WINEPREFIX=$PWD/pfx wine winecfg

   Chose "Windows 7" in the drop-down menu and click "OK"

Thanks a million, this got Resident Evil 5 up and running for me, along with the unofficial patch and disabling GfWL garbage. WMP install in protontricks is currently busted it seems, but this solution worked just fine the first time, just had to swap the steamid to the appropriate one (21690)