Hi Duncan,
there is a bug in the download when I try:
require(devtools)
chooseCRANmirror()
install_version("mvtnorm", version="1.0-8")
install_version("multcomp", version="1.4-8")
install_version("coin", version="1.2-2")
install_version("party", version="1.0-25")
Then I downloaded the packages from
https://cran.r-project.org (coin 1.2-2, multcomp 1.4-8, mvtnorm 1.0-8, party 1.0-25, sandwich 2.4-0, zoo 1.8-3) and copied them to $FSLDIR/fslpython/envs/fslpython/lib/R/library, but it's not working yet.