Paypal API integration problem

[need4speed]

Im trying to setup the Paypal API integration but it seems not to work.

In the Prestashop administration is says:

Prior to the use of the PayPal module, please check if Curl or openSSL are activated on your server.

Without SSL, PayPalAPI module will not be able to contact PayPal.


I have inserted the API information from paypal.com

But im not sure to choose: PayPal Integral or PayPal Option+ ?


UPDATED:
I guess its because i dont have a SSL certificate