Subsequence is a short puzzle-based campaign, supplemented with a subtle story throughout the game, set in a different universe from the canon of original Portal series.
The reason behind the testing procedure is still unknown, as are the goals the Enrichment Center is trying to reach.
Nice color scheme choice. Usually when a developer chooses non-classic "portal" colors for his modification - test chambers are starting to look gaudy, like a clown's workplace. But not your test chambers - your test chambers look nice, formal and confident.