After having installed sbt version 0.13.13 (with brew) on Mac 10.12.2 with scala 2.12.0, I tried the first example on the documentation (as per subject sbt new sbt/sca
sbt new sbt/sca
git clone http://github.com/scala/hello-world.g8.git
mv ./hello-world.g8/src/main/g8 hello-world
cd hello-world
sbt run
(assuming you have git setup)