Reviving Valve's 15-year-old e-book

Valve released a 15-year-old e-book that provides an interactive look into the development process of Portal 2. Priced at just €0.63, it quickly became a popular purchase among fans who enjoyed spending hours on co-op gameplay and Challenge Mode. However, unlike the game itself, which receives regular updates, the e-book has not been maintained.

The e-book utilizes Adobe AIR, but the version it installs is from 2011, causing various issues. Many features depend on external web services, which have since been refactored or abandoned, breaking the book's functionality. There are instances of domains expiring and being taken over by others or simply breaking due to lack of maintenance. The panorama viewers, which store assets locally, fail on newer Windows versions.

To address these problems, the author went through the e-book's files, decompiling SWF files using the JPEXS Free Flash Decompiler and writing a replacement ActionScript player using GPT-5.6-Sol. This allowed the e-book to play local MP4 files in place of YouTube videos. The author downloaded nine YouTube videos, resolving issues with three of them by finding archived versions or recreating them.

The e-book also contains interactive 3D visualizations and a minigame, all relying on dead URLs. After extensive searching, the author managed to recreate some of these elements. The book features music from iTunes, which can be found by copying the Apple Music link and extracting the final number. The author managed to download previews of all eight songs.

One notable aspect of the mobile version of the e-book is that it bundles all visualizations' code and assets locally, making it possible to extract and install the visualizations on a jailbroken iOS device. The author discovered a native iOS version of the e-book in an Archive.org collection and successfully installed it on their iPad.