For security reasons, after registering we cant let the user actually use the product until 14 days have past.
Right now I'm just appending a message at the end of the form (Ann#3) - is there a better way to do it?
I think that clear messaging to the effect of:
"We will email you when your service is ready. For security purposes this may take up to 14 days."
This helps me realize that I don't necessarily need to remember the '14 days' measure of time and can rely on my email - but you've also communicated an approximate wait.
I usually put this message after form is submitted: "... We've received your information. Your service will be available after at most 14 days. We will inform you about that.". This will attract user's attention.
But depending on your service maybe needs to inform user about your delay(before submit) or maybe needs to get user agreement about it. In this situation you should use a check mark with this title: "I agree to the terms of service".
i would also suggest to add a hyperlink for "Why i have to wait 14 days" or "Why it will take 14 days to activate"... and provide detail information or process of activation. user would feel better to get to know about the processes and detailed information would help him/her understand the importance of this process.