... Well then, not wanting to "burst anyone's bubbles" , but, perhaps, Adlice's "idea" of WinXP support is just what has been confirmed so far by your (and AstroSkipper's) tests: on-demand manual scans, only (i.e., you still need a Win7+ OS and a paid-for licence for real-time-protection to be effective); on a side note, Adlice's homepage doesn't breathe much confidence to me ; it appears they couldn't be bothered to change the copyright year to the current value:
https://www.adlice.com/roguekiller/
And, FWIW, the support forum (intended to help users of the "free" version) has been turned into read-only mode:
https://forum.adlice.com/index.php?topic=3890.0