I think, based just on the first episode, that I like the two part Titus Groan, with Sting as Steerpike, better than the new four part version, even though they have the same writer and the same excellent BBC acting and sound effects. In the books, which number among the greatest fantasy books of all time, the characters are introduced through action. The same is true of the earlier radio version which in fact, due to compression of two long books into three short hours, has a lot more action than the books. The new radio version begins by introducing the major characters, one at a time, and before they really do much. I suppose the story will pick up in episode two. They are, to be sure, great characters, wonderfully voiced: Lord Groan, Lady Gertrude, Fuchsia, Clarice & Cora, Barquentine, Swelter, Flay, Prunesquallor, and Nanny Slagg.
There is yet another dramatization of Gormanghast, a four hour BBC video version featuring such actors as Stephen Fry, Christopher Lee, and Ian Richardson. It's quite good.