I must admit that i did end up having to cancel the last couple of areas i had planned for time/deadline reasons. Without them, getting to the final room requires a fair bit of back tracking, which the game hasn't really asked of the player up until that point.
Also the last pick up is meant to open a new browser tab and navigate to a cat video on YouTube. I hadn't considered until now that people may have blocked that in their browser settings. I would have liked to have made a better ending, but again, deadline : (