Setting up RStudio Portable Default R version

Question

I recently discovered a portable version of R and RStudio @

http://rportable.sourceforge.net/

Open source rocks!

At any-rate, I am jumping from

Answer 1

I did not need to touch the registry.

I first installed R portable and then R Studio portable, both from Sourceforge. After launching R Studio for the first time, I was shown the option of choosing the installation of R to be used, as shown in

https://support.rstudio.com/hc/en-us/articles/200486138-Using-Different-Versions-of-R

I browsed to branch \PortableApps\R-Portable\App\R-Portable\bin, where executables are located. There I selected the 64-bit version.

If you want to change later the version used, you open R Studio and go to Tools -> Option -> General -> R Version.

This avoids modifying the registry, with the two advantages of Portable Apps:

1. Leaving no trace of the app in the system (or, at least, a much milder one).
2. Being really portable (or, at least, much more so).