I agree that it would be ideal to place gputools in a separate easyconfig (trying that).

Yet, the dedicated easyconfig does not do what it is supposed to and now get complaints on empty install dir; the build does work fine though after `module load CUDA R R/3.0.1-ictce-5.3.0-bare` and
`R CMD build gputools && R CMD INSTALL gputools_0.28.tar.gz`

To be precise, the above commands actually install inside a lib path of the R module itself, which certainly would not be the desired behavior for a factorized easyconfig...