I have purchased an Alkaline license. When I go to the certification request page, it asks me for a certificate. Should I install Alkaline first or can I get the certificate beforehand?

Before purchasing Alkaline, you should fully test it. Since all features are available in the non-certified version, there's no reason why you would purchase a license before actually trying Alkaline out.

Each certificate is unique. Certification keys depend on the machine's IP address and several hardware parameters. Thus, in order to request a certificate, you must install Alkaline first. When your hardware configuration changes, the certificate might not be valid any longer, you will have to request a new one. When moving Alkaline from a machine to another or changing the network parameters of the same server, a new unlock key will be provided at no additional cost.