I am having similar problems, after eventually getting power cms installed I can only get to the 4 stage of the log-in process and I am now being told that it cannot connect to my database.
I have deleted my original database and set up a new one, still with no luck.
I have also used cs menu writer for the navigation on the site - this has lost some of its formatting and has started to produce some wierd background images on roll-over, but worse than that all of my content has dissapeared, even when I view the site on my local machine. Fortunatly I made a back-up.
I have had a lot of trouble with this software, I am sure when it works it will be ok, but, I have almost lost a client by missing a deadline ( I thought power cms was the answer to my dreams...but is turning into a complete nightmare).
Having to pay for support for a piece of software that dos'nt seem to want to play is another cause for concern.........