Hi,
1. You can use the class add_in_progress which is added to the "add to cart" button while waiting for the AJAX request to come back. For example like that would hide the button while the product is being added:
.add_in_progress{ display: none; }
2. Are you talking about the carousel system ? With custom code, anything is possible but I don't see an easy way to do that with the current carousel system. The system is old anyway, and we want to redo it completely. So we'll try to at least have something where doing that would be easier but I can't promise anything as we didn't start any study on the feasability of the new carousel we want to have and we don't know yet how we would implement it.