OK, so I think the initial issue is that Mac is doing something funny to your keypress before passing it along.

How to fix *that*... I am not quite sure. I don't think the issue is Mac having a keyboard shortcut for "ctrl+r", because then I would think something totally different would happen. Might be worth checking, though.

Using driver scripts can be great. This tutorial case provides some nice examples of features to control with scripts:
[afni.nimh.nih.gov]

If you really want to use keypresses in vivo, but Mac is causing problems (typical...), you could try to open up the image and just use your computer's screengrab capabilities. On Mac, it is something like shift+command+{1,2,3,4}, I think? In truth, that is a bit close to what SUMA does anyways-- it captures at screen resolution, so making the image "big" effectively makes it higher resolution in the end (because whenever you publish/use it, it will be shrunk+condensed, becoming higher DPI).

--pt