[R-SIG-Mac] Installing R-devel from http://r.research.att.com/

[Seth Falcon]

Hi all,

I suspect this is an easy question...

How do I install R devel from the various snapshots provided on
http://r.research.att.com/.

[I generally build from source, but need to assist people in getting a
working R-devel on OSX for a course we are teaching]

The website says:

    The installer image (*.dmg) is packaged exactly the same way as
    the CRAN release of R (including the GUI) and it will update your
    R version (unless you delete the last receipt). 

The installer image is too small to contain everything (52kb) and I
don't understand what is meant by "unless you delete the last
receipt".  I've tried the installer and it tells me it can't open
R.mpkg.

Thanks,

+ seth