Try not to rush the input too much otherwise the roll might come out by accident. You can delay the second 2 in B22 longer than you'd think. It might be easier to think of the input as B2FK...2, DB1 instead. Also I find using the extended range version of B2 in combos much easier than micro-dashing after the BF1 but some people probably won't agree with that. Last tip would be to practice the combo using 22 as the starter to begin with so that you don't need to worry about micro-dashing or using the extended range B2. Hope this helped
He used to get really good damage with Havik, but unfortunately it got nerfed around the same time Cyrax got nerfed. I haven't really tried him since he got buffed but I know he's got some good HtB setups with Havik now. The main problem I had with him when I last tried him was the recharge time on Darrius after every combo costing full Kameo meter, meaning you had to go most of the fight without a Kameo. But now that he's got that new ambush move for half Kameo meter I might need to test him out again.