This is a bit of a strange program...
Installation adds the program's folder, with 24 files, 1 folder, 36.5MB, plus under [UserName]\ AppData\ Local\ it adds an "Apps" folder with what appears 2 randomly named folders with one "manifests" file. In the registry it adds uninstall entries, QT cache entries, & an unusual set of registry keys with a random value entry at: [HKEY_CLASSES_ROOT\Software\Microsoft\Windows\CurrentVersion\Deployment\SideBySide\2.0\
Once activated the app seems to be portable -- I copied the activated program's folder to a fresh XP VM & it runs & is registered.
The maybe strangeness -- perhaps unusual would be a better word -- is that activating the app breaks the InstallWatch Pro program I use to monitor these apps in an XP VM, with a crash when taking the 2nd snapshot. Running the activated app without installing it breaks InstallWatch Pro the same way -- I have to restore the VM to get InstallWatch Pro to work again. If I don't have InstallWatch Pro running, I can run the not-installed app & afterwards InstallWatch Pro is fine. Using Regshot, I don't record anything unusual after running the not-installed app. While nothing should be running once I close the app, & nothing shows in Task Mgr. or Services, attempting to move the program's folder says it's still in use, *after* every file in that folder has been moved (?). Shutting down XP in that VM, I get the dialog that Undelete.exe is still running, with the End Now or Wait buttons.
So... Installation seems harmless -- I have no idea what activation does, but it does change something that breaks at least the one app, but only if it's running at the time. It's probably nothing serious, but it bugs me, because whatever it is I haven't a clue. But OTOH I've got no real motivation to find out either, since undelete apps are not rare thanks to GOTD, so there it is, what I've found, in case that helps or interests anyone.
BTW there were comments re: what's limited about this standard version -- from the About dialog:
Unable to detect and recover files by their signatures;
Disabled restore deleted partition feature;
Disabled advanced Disk Editor tool for raw disk exploring and editing;
Disabled Partition Manager - robust feature to create, modify and resize disk partitions (volumes);
Disabled create virtual RAID assembly feature;
Disabled Recovery Wizards - self-guided tools for easy data recover;
Disabled Disk Images - comprehensive feature to create and use disk images;
Disabled File Organizer;
Scan results can only be saved;
On a side note, checked the 2nd GOTD, HippoEDIT, which was the main reason for firing up the XP VM to start with... "1979 registry entries added" -- Hippo is right. ;)