During bottles setup, when trying to install windows dependencies on the bottles wine prefix via the terminal with the line:
WINEPREFIX={your-prefix's-path} winetricks cmd d3dx9 dx8vb d3dcompiler_42 d3dcompiler_43 d3dcompiler_46 d3dcompiler_47 d3dx10_43 d3dx10 d3dx11_42 d3dx11_43 dxvk quartz
There is a chance you may encounter errors like
warning: wine cmd.exe /c echo '%AppData%' returned empty string, error message "wine: '/home/your_user/.var/app/com.usebottles.bottles/data/bottles/bottles/bottles_gamma_prefix_directory' is a 64-bit installation, it cannot be used with a 32-bit wineserver."
And then the terminal hangs and does not let winetricks install the dependencies.
The new alternative terminal command could look like:
WINE="{path-to-proton-downladed-by-bottles}GE-Proton(x-y}/files/bin/wine" WINEPREFIX={your-prefix's-path} winetricks cmd d3dx9 dx8vb d3dcompiler_42 d3dcompiler_43 d3dcompiler_46 d3dcompiler_47 d3dx10_43 d3dx10 d3dx11_42 d3dx11_43 dxvk quartz
{path-to-proton-downladed-by-bottles}GE-Proton(x-y} can be easily found by exiting bottle, opening bottles preferences, in the "Runners" tab next to the ge-proton version that's already downloaded there is a folder icon which opens the location in the file browser.
Note the location is appended with /files/bin/wine to select the ge-protons wine prefix.