My website has been hosting downloads with alternate versions of the compiler and ide for nearly 15 years now. I also have published JsonTools, BareGame, TinySim, the original Shell Controls, and lots of other packages for the Lazarus community. The install scripts at https://www.getlazarus.org/setup simply download a seed compiler, the sources, and builds, while making certain it does not interfere with user's existing setups by restricting configuration settings to your chosen install folder. In other words, you can run my version and your existing version at the same time without any problems, and if you don't like my version the uninstall process is to delete a folder, and perhaps a shortcut if you copied it anywhere.