The "{embed:tilename}" feature doesn't appear to be working for Fin exits - the preview works as expected in the editor, but when the exit is triggered in the web player it just shows the raw text. Which of the two is incorrect? (i.e. on a real device will the ending display like the editor or the web player?)
This was fixed two weeks ago (The Pulp Changelog - #5 by shaun). You might need to clear your browser's cache and you definitely need to redownload the pdx to get the fix. If you already had embeds in fin exits you will need to edit those exits so the editor can parse out the now supported embedded tiles.