Benson,
There's no problem upgrading a package if you have changed the name of a file, it's as if you have removed it - it'll in any case simply write a new version of the original file (in other words, re-installing the upgraded application, and leaving your original renamed file in place). Exactly the same will happen when you rename (move) the rc.d script though, so the two ways of disabling the crawler are equally "bad" seen from the point of DPKG.

pixelseventy2:
So far I'm not aware of any side effects of disabling the crawler, but then again I don't keep media player running. Whenever I want to watch or listen to something I start it via the file manager, which is how I would always use a media player - and as the Nokia-provided one doesn't have a built-in file manager, I simply use the normal one.