This is one of those apps from BinaryMark that was interesting to figure out what's going on when you 1st run it. As for the app itself, I can manage the 5MB of disk space in case it comes in handy some day, and I imagine there's maybe a 50% chance it might.
When you run the GOTD setup.exe, BatchWordReplaceSetupG.exe is copied to a folder in the User Temp folder & run [you can copy this elsewhere if you like]. Running that more or less installs the app in Users\ [UserName]\ AppData\ Local\ BinaryMark [you'll also get a new BinaryMark folder in Users\ [UserName]\ AppData\ Roaming\]. That's the so-called Portable mode. Installing the app puts those same files in whatever folder you select, adding a file for uninstall & a shortcut to the web site. Both portable & installed versions add a registry key to [HKCU\ Software\ Microsoft\ Windows\ CurrentVersion\ App Paths\ -- the installed version also adds an uninstall key.