Question: how to combine crt and key?
Answer: Click the topmost certificate (In this case VeriSign) and hit View Certificate. ... 
Select Base-64 encoded X.509 (.CER) certificate.
Save it as rootca. ... 
Rename it from rootca.cer to rootca.crt. ... 
Here is where we need OpenSSL. ... 
The command syntax for my example is: