A: This is the project I've got in mind - (weblink) schamberlain.github.com/2012/10/rgbif-newfxns/
B: Here is their GitHub - https://github.com/ropensci/rgbif
C: My machine: i86-64bit, Windows 7, R. 2.15, RStudio 0.96.330
Following their instructions, I perform the following:
a) Download & Installation of Rtools 2.15 (weblink) cran.r-project.org/bin/windows/Rtools/
this step is plain sorcery to me, I am just following the instructions given in the "Windows toolset" appendix (weblink) cran.r-project.org/doc/manuals/R-admin.html#The-Windows-toolset.
In the end I've got this nasty C:\Rtools folder in my system, and the PATH variables (no idea what this is) are set as the appendix suggest (as far as I can say).
b) in R: library(devtools)
c) in R: install_github("rgbif", "ropensci")
This will produce some notification output and ends in this Error message (its a pastebin.com snipet of the output).
I am not sure whether or not it is possible to help with the provided information. Also I am feeling there is something missing between (a) and (b) - b/c I can't see a package 'Rtools' afterwards in R - maybe thats how it's supposed to be, how should I know?
I should add: In my default library folder .../Documents/R/win-library/2.15 there IS afterwards an un-zipped folder "ropensci-rgbif-60c74ca" with all the needed files in it! But I can't access it from within R.