Sorry about the trouble you're having.
Sharing your Rcpp installation attempt error messages would be helpful.
Rcpp occasionally has trouble installing because a C++ compiler isn't present on your machine. If that's the case, the complier you need to install depends on your OS
- On Windows, install Rtools.
- On Mac, install Xcode from the app store.
- On Linux,
sudo apt-get install r-base-dev or similar.
However, the above advice is just guess, knowing a bit more about the errors you're receiving the system you're on would be helpful.