The package r-cran-gwidgetstcltk 0.0-55.1-3 has been added to kali-rolling. It has been imported from Debian: https://tracker.debian.org/pkg/r-cran-gwidgetstcltk -- More information about r-cran-gwidgetstcltk: http://pkg.kali.org/pkg/r-cran-gwidgetstcltk