Cube Cart Error and SSL Certificate set up

I have cubecart 3.20 I have my shop ready to open and add new items but I am running into 2 problems and can not open my cart yet ... I have researched and tried everything I know what to I will admit I do not have any experience much with shopping carts just basic HTML 1: I need some one give me quote to help me set the SSL certificate & website up , and to correct a error I get on the ( conform page ) when I finalize a test payment through paypal the error message . the payment goes through to paypal and the cart ok... but when it takes the customer back to the shopping cart to thank them & confirm the order went through it gives a error "Sorry, your order failed!You can attempt to purchase your basket contents again below:" instead of saying the order has been placed and the cart does not empty 2: the SSL I tried to set the SSL certificate up and I accidentally put in the wrong info and lost my shop & control panel had to use the web tool to get it back .. the webhost is saying I have the SSL running but I might need to adjust a code in the pages or control area thank you