No. I've never successfully used CombineZM. If I remember correctly, this was a single shot and I just got lucky that the refraction was in focus at the exact same distance as the grass blade. I have done some of these with 2 focus points - one for the refraction and one for the blade, and just manually layer mask blend them together. Don't think I needed to for this one, though.
Re: CombineZM - have you checked out
Zerene Stacker? I haven't done much macro lately, but I've heard good things about it. I know Brian (LordV) was at least testing it out, not sure if he's gone back to CZM or not.