Hi. Buddy John and I took our starter kits (Epoque ES-150 and Canon S40/Fujifilm Finepix using fibrecable) to Truk two weeks back. The Canon housing and I both survived a 56m dive (it was rated to 30) and I learned a little more about lighting.
Well the results are pretty darned shoddy but I think we began to improve (in my case the closer I got to the surface light that is ;-) ).
http://psg.mmdc.net/gallery/trukdive
For me, overexposure was the main culprit (when the flash fired) but I started to get the hang of the GN setting towards the end. Under those conditions and without a wide-angle I guess it never needed to go over GN5 anyway.
The biggest pain (and many report this with the S40) was the lens fogging up after 40 minutes in 30-degree water. I found that keeping the whole thing wet and shaded prior to the dive seemed to help but it sure was annoying. Antifog seemed to make things worse - maybe I didn't use it correctly.
The movie mode was actually quite useful and I wish the resolution could be slightly better. Ok we know I should use a digicam for that but just a slight improvement and maybe an auto-f/white balance would've been good.