So, the program needs administrative privileges and to be run at computer startup? Usually, I'd say that rather than blaiming UAC, this sounds like a job for service + GUI. That's generally the correct way to do something like this, and has been since NT4 or so.
"Everything" is a bit special, though - from their FAQ (especially the point about only working with NTFS), I get the idea that instead of normal filesystem traversing APIs, they're directly reading the MFT... this means that prior to Vista, it wouldn't have been possible to use from a limited user account without a "runas" application, and UAC thus acts as an enabling
If the developers want to play clean, the fix is pretty simple - don't read the MFT until the first the search GUI is invoked, and only ask for UAC elevation for the duration of the MFT read; the application shouldn't need to run with administrative privileges outside that operation.