Hi,
1. xxM 0.6.0 is compatible with R 3.2.0. You can install the package using:
install.packages("C://path-to-download//xxm.zip", repos=NULL).
Alternatively, you could use Rstudio to install the package.
2. A new version of xxM compiled for various versions of R will be released shortly. It will include new features.
Best,
Paras