I have seen the code to embed a hyperlink, but can you embed a game you make in GameLab into your app that you create in AppLab? Also, the code below only works on the home screen. Can you tell us how to put it on another screen?
At this point in time, Game Lab games cannot be embedded into App Lab.
Unfortunately I believe the code you referenced:
write("<a href='http://code.org/csp'> go to CSP! </a>");
does only work on the home screen. However, our engineers are currently working on a block to link to outside webpages. I don’t have any information on specific dates or when it will be released, but I wanted to let you know it is in the pipeline and we know how valuable this will be to many of our users.