Here's an article on wireless flash http://www.friedmanarchives.com/flash.htm. It was originally written back in the Maxxum film days, but most of it is still valid except the ratio flash function is disabled with DSLR's.

I'm not sure if that article talks about power settings or zooming, but I think it's the most useful article for anyone using the Minolta/Sony flash system. Wireless is where the system shines, and that article is very good at explaining it.

Edit: I see now that the article has been updated for digital..