Forum OpenACS Q&A: Response to OpenACS 4 on Mac OS X (and Darwin) HOWTO now available

Yeah.  I suspect this is because you downloaded or edited tthe
file with GUI tool which uses the traditional Mac carriage return
symbol (thus the ^Ms), but the unixy side of things expects Unix
style carriage returns.  Drag. There is still a bit of a disconnect
between Aqua and the underlying Darwin way of doing things

Anyway, there are tools to convert back and forth.  However, I've
never used them.  I just open the file in emacs and replace ^M
with returns where needed.  I think this shall work in this case.

You could also explore TextEdit, I think it might have something
in its preferences for how to save files.

Good luck,