As far as i can remember it does update the windows path. If you
installed to c:\ruby192 then c:\ruby192\bin should be in the path
You can check echo the path in cmd.exe (Command prompt)
echo %Path%
Can test in cmd.exe using the following which will give you the ruby
version
ruby -v
Remember you normally use ruby to run a .rb file so should be able to
run if ruby is on the path using the following from the shell
ruby app.rb
RubyInstaller by default will not associate the .rb scripts or add
Ruby to your PATH. You need to check the two boxes during installation
that tells you "associated .rb and .rbw" and "Add Ruby to the PATH"
You can install over your old installlation and check these.
Please remember to close any existing command prompt Window as PATH
changes do not propagate inside them.