When I run this I get an error that the org.racket-lang.prefs.rktd file can not be read.

[mvidal01]

The full error is file-or-directory-modify-seconds: `read' access denied for /Users/mvidal/Library/Preferences/org.racket-lang.prefs.rktd

The permissions have been opened up. ls -l shows
-rw-rw-rw- 1 root staff 1733 Jan 1 13:45 org.racket-lang.prefs.rktd

[voila]

The owner of org.racket-lang.prefs.rktd is root ?
Did you try running

$ racket main.rkt 

as root ?