This toolkit is using Ruby 1.9.3 . This Ruby version is not compatible with our current TLS 1.2 support.
As stated in this toolkit page, it is provided as-is and is not supported.
We did find that upgrading the Ruby to version 2.2.6 which is the current version that's working with our connectors past the deprecation notice, we did find it to work with this toolkit and fix the errors. You can download Ruby 2.2.6 from: https://www.ruby-lang.org/en/news/2016/11/15/ruby-2-2-6-released/