With the Nudge set to arrow keys only (not Option+arrows) the arrow keys work as advertised for X and Y; for Z movement it’s fn+arrows (up/down). (In Windows it’s PageUp/PageDown to move in Z, but these keys don’t exist on a Mac keyboard)
As in Windows, there are also 3 different distance values possible for nudge: arrow only, shift+arrow or ctrl+arrow. These work as advertised in the X and Y directions as well, but fn+shift+arrow does not use the shift+arrow nudge setting and move the object in Z, instead it zooms the viewport… Oversight?
While it’s rendering, re-read my post… It’s maybe not totally clear. What I’m saying is that fn+shift+arrow does not work as it should. I have a “wired” keyboard, but no page up/down keys because it’s “wired” to a mac portable…
The Apple keyboard that has a numeric keypad also has Page Up, Page Down, Home, and End keys. On a keyboard without a numeric keypad, fn-Up Arrow is the PageUp key and fn-Down Arrow is Page Down. See http://support.apple.com/kb/ht1343.
There is a Rhino keyboard shortcut for Shift-PageUp; it is Zoom Lens In. On the Mac, these were being handled before the arrow key nudge actions were handled and this prevented Shift-PageUp from working as a nudge command. This will be fixed in the next WIP release.