I use R under Windows on several machines.
I know you can set the working directory from within an R script, like this
setwd(\"C:/Documents and Setti
I put the following line in front of my scripts and it allows me to work across my computers.
setwd(path.expand("~/path/to/working/directory/") )
where ~ is = to your home directory.
Sys.setenv(HOME = "path") or Sys.setenv(R_USER = "path") can both set the home directory.
In my case, I work on several windows boxes, each have fairly different directory structures, but by setting the home directory properly I can sync code between computers and have them run properly on each one since where I run my R projects have similar directory structures.