Welcome, @Frodo,
First rule of the thumb: DO NOT use AppCleaner (or any other similar app). It can do more damage than good, especially in an automatic mode.
You can safely delete older versions of RW app, if you don’t intend to use them anymore (you can always re-install them, if necessary).
P.S. Take a look at this thread to see how to find files created by previous versions of RW.