WineGUI has been released in version v4.3.0.

WineGUI is a user-friendly graphical manager for Wine on Linux.

The update moves GE-Proton runners onto a UMU runtime managed by WineGUI itself, instead of relying on the Wine binary embedded in the runner.

GE-Proton runners use a WineGUI-managed non-Steam runtime for Proton initialization, bundled components, and protonfixes. WineGUI downloads and verifies its small launcher component automatically under ~/.local/share/winegui/umu; users do not install or configure it themselves. Steam is not required. WineGUI never falls back to launching GE-Proton’s embedded files/bin/wine directly when the managed runtime is unavailable.

GE-Proton is available for win64/WoW64 bottles through its complete managed runtime. Proton removes WINEARCH during initialization and cannot create a true win32 prefix through its supported launch path, so WineGUI does not offer 32-bit Windows versions with GE-Proton. Choose a regular Wine runner when a true 32-bit bottle is required.

Source: GitLab