Your Sinclair: Castle Thade Revisited - Rated 8/10 by Mike Gerrard. Plenty of extra little responses have been built-in should you try doing things that aren't going to get you anywhere, and all-in-all, it's well worth sticking your hand in your pocket for.
Meta Description: [ Castle Thade Revisited review, by Mike Gerrard from a Your Sinclair tribute site, with game reviews, and loads of other groovy stuff. ]