I'm playing with the spotify play button and try to make it display an arbitrary set of tracks, that I'm giving as a comma-separated list of IDs.
It works well most of the time, but it can happen that the button is not properly rendered, and displays the Spotify Developer Page instead, like shown here: http://xben.free.fr/spotify/
I feel like it happens when using an important number of tracks (more than 80).
Has one of you experienced the same problem, or know if there is a limitation? I went through the doc and it only mentions a 1000 tracks restriction when using an existing playlist.