Once I followed ecib's lead and got the proper command line tool, it found GCC fine. Then I followed the directions and nothing happened. Then I fed in your little string (once I determined that the $ isn't for me to type - as I said, not good at computer) and magic compiling and things happened.

After much putzing around and determining that double-clicking the SaVi executable, I get:

SaVi: For 3D visualization, run from within Geomview. SaVi: defaulting to J2 orbital model. SaVi: $SAVI was not set to location of savi directory containing launch script. SaVi: $TCL_LIBRARY was not set to location of directory containing Tcl. SaVi: $TK_LIBRARY was not set to location of directory containing Tk. SaVi: edit and run the savi wrapper script in savi's directory to set locations. SaVi: tcl_error: invalid command name "app_init" SaVi: tk_init: Error in app_init: invalid command name "app_init" SaVi: could not initialise Tk (main: error in tk_init). SaVi: Error! Exiting.logout

[Process completed]

...and now it looks like I need to run geomview. Which looks to be more of the same.

At this point I begin to ask if this would be easier if I threw Ubuntu on the spare macbook I have gathering dust...?