R executable

The location of the R (or R.exe) executable to run for R transformations

If you leave this setting blank, R will be picked up from your PATH variable, which will work for many users. However, not all users have R on their PATH, or they may want to use a different version of R, so you can specify the R path here.

R library installation

Selects whether to use a directory in the user profile for installing R libraries

Some of the R transformations you run may require installing an R library. Not all users have access to install R libraries in a central location, so the default setting is to leave this ticked and install R libraries into a per-user directory inside the Columnal settings. Untick if you want the default R installation behaviour (see the install.packages and .libPaths R functions for more documentation of the default behaviour).