Unlike other OSes, Amiga OS is rather well documented. There is no effort to hide parts of the OS (like the registry, if fact, there is no registry. Count your blessings!).
It won't help you now, but for the future, another solution (habit) that is useful is to let the installer create a log file (and store it with the installed application), especially if you are trying it out. If you latter want to remove the app, the log file documents all of the changes made to your system partition.
When I make a fresh install of the OS, before installing other enhansements, I comment (with say, "OS3.1") all of the original OS files (in L, Libs, Devs, C, etc) so I can distinguish them later on a crowded boot partition.
Likewise, when I install manually, I comment the new files with notes (like the package that requires them).
Food for thought.