Does anyone know how to change unit stats, i.e.. damage, speed, range, etc. on a mac?

Have you tried running the Mod SDK?

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It's an exe file, which doesn't run on a Mac. I'm just wondering if there is a file I can tweak in a text editor. I'm not wanting to run parallel desktop or anything like that in order to open the exe file.

There are XML and LUA files you can edit in a basic text editor. But you need to compile (using batch and executable files) them in order for RA3 to recognize them. So it sounds like you'll need to run Windows in a virtual machine in order to do any modding yourself.

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