What if renoise looks in the preference folder for metronome.wav and uses that instead of the built in one.
This would save you digging through the application folder and replacing it each time it updates.
Also when ever you jump from one version to another it would copy across like the config settings.
my vote too.
I more used to the fourth high pitch tick metronome rather than the first high pitch tick metronome.
Also it be nice if Renoise would come with a couple of different default metronomes, f.e. also a low freq kick-like metronome.