There is no register link because posting in forum requires you to have an Edgebee account (same login and password used).
Linking your Kong account to Edgebee is currently not supported, but as a workaround, you could register a new account, verify the (different) email and then use that account to post.
if you play on edgebee website – you need to go to the top of page, here you will find your name and an edit tab, click on edit.
you now need to ensure you have an email address in the contact email address box.
you should be able to log into the forums – if there is an email address on your account.