The game runs surprisingly well. You can download the DRM-free version of the game from BioMedia Project. The files are hosted with the permission of the LEGO Group. The only fix I did was enabling widescreen support with modern screen resolutions. The instructions for that are here.
Yeah it runs pretty well in Proton. I’m using the Heroic launcher. I had to Use Wine-GE to run the installer, otherwise it kept failing. After I installed it I set it to use the latest Proton-GE. It runs just as good as it does on Windows.