Did you do as it said in the txt file that came in the download "Create a new user account at the setup wizard as requested"?
The txt file instructs this:
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Installation
Unzip the package you`ve downloaded and install the software.
Create a new user account at the setup wizard as requested and log in
with the emailed password. Click the "Convert coupon code" link at the bottom
of the following licenses screen and enter the code.
(The code is in the txt file.)
Follow the wizard instructions to the end.
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If you're worried about getting your email spamed then just quickly set up an on the side email just for this at yahoo or hotmail or some other free email service. Always good to have a extra email for these reasons.