I just switched over to the xz-1 this summer (only because my other camera flooded). I already had the S2000 and subsee +10 and paired them all up down on the Turks and Caicos the end of June. I have never had problems with focusing when shooting supermacro until this past trip.
I shoot manual with AF and macro mode all the time. I found that it was very difficult to get this camera to focus on my really close up shots so just recently bought a little nano focus light to use on my trip down to the caymans... leaving Friday and will be diving by Sunday. I also bought the subsee +5 to bring along.
From everything I've read and people I've talked with, the focus light will really help the xz-1 AF to work, especially for supermacro.... but will let you know what I think while down there.
However, in answer to your question..... I would start off with a close up lens first. You don't need to set the camera to manual focus... AF is fine. Just play with it.
For the most part my setting is manual, AF, macro, F5.6 and 1/200.... I have my strobe set to sttl and the camera to force flash. Will be trying out the 1/16 flash setting on this trip and if needed, play with the exposure on the inon.
I have pics taken with this camera in my T+C facebook folder.
