i haven't seen The Mindscape of Alan Moore, but the NY Sun's review of it sounds like a fair criticicm of all previous attempts to represent Alan on the small screen:

Mr. Moore's interview is great stuff; with his droopy eyes and bushy beard, he looks and sounds like a talking British bear who spends his days fixing car engines and his nights philosophizing. But the film spends too much time worshipping at his feet, rather than expanding on or challenging his views, and it embarrassingly reproduces scenes from his comics in bargain-basement eruptions of misplaced fandom that are mortifying to watch.