CSS/Formatting & Features

I am using the Karma theme currently, but even with a simple theme, I am still seeing formatting issues even when using the "None" option for styling in the MarketPress Store Settings page. The items that are frustrating are:

1. Button Text is Too large or being cut-off in view.
2. Billing and Shopping Cart display is laid out poorly. Shopping Cart is centered while Billing info is left aligned, Order Total is left-aligned while Order information is centered, etc. Where is CSS being controlled for these individual pages (Shopping Cart, Checkout, Order Confirmation, etc).
3. Is there not a Continue Shopping option when viewing the Shopping Cart page?