2) The shopping cart module will not show the shipping costs added on.
3) The css for the front end is totally disconnected so you can't control how it looks to the customer (I even deleted the css directory from /components/com_caddy and it didn't affect it).
I like the fact that it uses a snippet of code injected into an article for the product description; this way I don't have to use a single store front page with clickable categories, and I can control how the images are displayed. I also like the fact that it can be used for smaller stores; but alas, there are just too many bugs and non-functioning aspects of the cart to be worth using right now.
[EDIT] someone beat me to the quantities not updating complaint but I think it's worth mentioning twice.
I will repeat my previous answer to the previous comment. You too are very welcome to submit your questions and get answers from the very active forum.
As for the css, the demo site describes in detail all the possibilities of the css. If your installation does not load that css, there is a problem on your server, not with the simplecaddy program.
Welcome to the forum!