I just noticed after a fresh update that lots of of my old DVDs did not work in show.php any more (just returned Internal server errors).
I boiled it down to the imdbID-entry in the database, which contained "engine:id" entries of an engine that was removed some time ago. I never removed old files until now, but only overwrote the updates files. That's why I did not notice the error sooner.
I can (and will) fix that in SQL to replace the imdbID-entry in my database. But I think video generally should not fail to display those old entries at all, so I created a patch where the engine is only included in engineGetContentUrl() instead of being required. After the include its checked anyway if the function $engine.'ContentUrl' exists.
fix for this bug