Monitored installation / activation in my Win11 VM, then ran a disk check on the C: drive. The app said all was OK, but Windows popped up a warning that a restart was needed to repair the disk. The chkdsk scan/repair that ran after restarting seemed to proceed normally, but after a restart Win11 stalled before bringing up the log-on screen. Powered off, started Win11, and it went into self diagnostics because something got broken. I had just restored the VM's VHD from backup before I started working with it this evening, so it's almost certain the backup copy was identical [except for CheckDrive 2023] to the drive that reportedly had the error. Restored the VHD again [just a copy/paste] and booted into Win10, and from the Command Prompt running as admin, ran chkdsk d: /f [check & repair], getting no problems found.
Now this was all using a VirtualBox VHD [Virtual Hard Disk] rather than a real physical hard disk, so that may be why, but I don't know how the data [Windows] on the drive became damaged, so out of an abundance of caution as they say, I won't be trying this on any real hardware.
That said, the app adds the program's folder, a ProgramData\ XDMessagingv4\ folder, Abelssoft folders in both Users\ [UserName]\ AppData\ Local\ & Roaming\, plus 6 versions of the SegoeWP font. The only change worth mentioning in the registry was the expected uninstall key.