http://www.dr-lex.be/software/rott.html

This may be the version you found but it says it's a universal binary so it should work. But since I only read the topic title first before I posted and then saw you had an OS X build i don't know if this was the one you used. Theoretically this one should work.

It does mention you need the SDL libraries so make sure you get those.

libsdl.org

I did check and it runs fine on Yosemite(10.10).

You will need sdl 1.2(not 2.0) and sdlmixer 1.2(not 2.0).