Hi! There was nothing to download on GitHub until today - the repository had only source code, no releases. That is fixed:
https://github.com/fundacja-reborn/r...eleases/latest carries re-read-0.5.30-chromium.zip, the exact package that is in the Chrome Web Store as 0.5.30 (SHA-256 in the release notes), and every future version will have one too.
To install it: unzip the file, open chrome://extensions, turn on Developer mode (top right), press Load unpacked and pick the unzipped folder. The extension stays installed across restarts; Chrome only shows its usual notice about developer-mode extensions on startup. Chrome/Chromium 128 or newer; Brave and Edge work the same way. (Installing a .crx directly is not a way around the store in plain Chrome - it refuses packages from outside it unless an enterprise policy allows them - hence Load unpacked.)
Your "Download interrupted" fits the restricted network, by the way: the store page is chromewebstore.google.com, but Chrome fetches the package itself from a different Google host (clients2.google.com / clients2.googleusercontent.com), so an allowlist that shows you the store page can still cut the actual download.
One more thing for a machine that only reaches certain addresses: translation models are downloaded from storage.googleapis.com, only when you press Download in the settings. If that host is blocked too, fetch the model files on another machine and use "Add a model from files" on the settings page - gzipped files can be used as they come. Dictionaries have the same "Add a dictionary from files" option.