I encountered this problem and there was no clear explanation about how to work around this bug.
The latest version of R (v. 3.1.2) for OS X Mavericks freezes in Yo
The newest version (Wooden Christmas Tree 3.2.3 and the GUI 1.66) that were released on December 10, 2015 appear to have corrected this problem. It does require you have Maverick or newer OS. I've only performed limited trials, including opening with the GUI rather than through terminal, and have not had any hangs.