GToolkitLauncher lets you keep several versions of Glamorous Toolkit around, and run each of them with ease. A bit like pyenv for python, or rustup for Rust.
Install Glamorous Toolkit. On the 'start page', in Local Knowledge Base choose 'Add new page'. Call it something like Environment Setup. Add a Pharo block, and copy this in:
Metacello new
repository: 'github://StephanEggermont/GToolkitLauncher:main/src';
baseline: 'GToolkitLauncher';
loadThen add another Pharo block. Copy the line below, to load the rest of the installation instructions inside the Glamorous toolkit environment:
BaselineOfGToolkitLauncher loadLepiterAt the bottom of your Environment Setup page, you will now see Documents/lepiter/default. Lepiter is the name of the documentation software. Click on there, to select

After clicking on this, the documentation will show up in the 'Pages' view on the left, as part of the history of contents.
Open the GToolkitLauncher page to continue your Glamorous Toolkit journey.