I am unable to install 5.8.1 via GetIt. When Setup gets to the "Embarcadero RAD Studio for Windows" is running and needs to close step, it fails to close Rad Studio. If this step is ignored, then it fails at a later step when trying to replace a DLL (because Rad Studio is open). I am unable to close Rad Studio gracefully myself because the GetIt package manager is running (installing Twine).
It appears that the only way to upgrade is to uninstall first, which is problematic when previous versions of the IDE are installed.
Workaround:
1. Copy the existing Twine directory in Program Files (x86)
2. Uninstall Twine in the IDE.
3. Install Twine.
4. Copy other DLLs/files from the previously copied directory into the install folder as needed.
One other mention: The window title in the installer still shows 12.1 instead of 12.2.