Does the AppleWWDRCA.cer have any bearing on developing certificates using OpenSSL? If so, what? If not, what is it’s use?
Edit:
I am using Windows. I do not need an answer concerning Mac development.
So far, using OpenSSL, I have created development apps (signed, and with certificates), ad hoc apps for multiple developers (signed, and with certificates), and they all have worked just fine. This is (probably) only a question about whether it is needed to put an app in Apple’s App Store.
No, the WWDR Certificate is only used to authorize your app for selling/integrating on the Apple App Store.
Public OpenSSL certificates are (generally) given to your application from an outside Certificate Authority and used by your users to authenticate (prove that your application is indeed what it claims to be) your application and encrypt the data they send in a SSL connection. These can be generated entirely independently of your WWDR certificate.