Problem with woocomerce

Hi there

The 40mb thing is the memory allocated to your site from your ISP and usually can’t be overcome without shelling out a lot more money needlessly – unless you expect mountains of traffic all at one time, or you have hundreds of products in the system, I wouldn’t worry about it until your empire expands!

Can’t really help you with the checkout at the moment because that could be any number of things! Can you give us a site url to take a look?