Products not in cart and odd formatting for MarketPress page

We're really enjoying how this plugin is turning out on this site. But we're challenged by a couple of things too.

From the initial store page, if someone adds something to the cart, it doesn't work. It says it does, but nothing happens.

Really, we'd be fine without this page, since the products page lists all the products anyway. But that doesn't seem to be an option, so we're trying to find ways to make this page work within the framework presented.

For some reason we can't seem to get a decent format for the products page - As you can see, all the products are in one continuous column. I haven't been able to figure any way to change it. We've played with various display settings, but nada.

When adding items from here, they don't go into the cart either. I have to go to the actual item page in order to get something to go into the cart.

Now I'm testing it again, and nothing will go into the cart from anywhere. Heh, did I mention that I'm confused.

And is there a way to make the shopping cart more prevalent? More readily accessible?

The plugin is pretty nice. We're just needing some help with these issues.