Using IconCopier with the bug that I mentioned could make the system unstable. It's an old tool and I don't know if Mark Ritter still supports it with bug fixes.
Usually, RemLib should be executed before the first program tries to access icon.library. On Aros 68k IPrefs seems not to call icon.library as it is done on AmigaOS, so you're lucky and it may work even from user-startup. But in case that any program opens icon.library before RemLib is executed it would load it from the Aros Rom into memory and installing my library later from Libs: may fail.
The transparent disk icon in your video could be a ghosted deficon, a disk without an existing disk.info file. If your don't like that you could add the tooltype "NoGhost" to Envarc:Sys/def_disk.info (or what it is) or use "IconGhostingOff".
You are trying to rename some icons in your video with Icon->Information by changing the path. Nobody says that this would work. Why don't you use Icon->Rename instead? There is nothing at the path "Ram:downlod" and it should fail.
Sorry, concerning Alerts and Crashes of Wanderer I can't help you, that are covert Aros features, I guess ...
