Cannot purchase activation key (Bizagi Modeler)

When clicking the Buy Now link as described in http://help.bizagi.com/processmodeler/en/index.html?company_logo.htm

I just get an empty page and no option to purchase the key.

Steps to reproduce:

1. Install Bizagi Modeler version 2.5.1.1 64bit

2. Register the product with Bizagi user name

3. Go to File>Options>Documentation

4. Click on Configure logo used for Documentation

5. Click on the "Buy Now" link

Expected Result:

Bizagi Webpage opens where the activation key can be purchased.

Actual Result:

Empty page on the Bizagi webpage opens, which no option for purchasing a key.

See attached Screenshot. I tried with IE, Firefox and Chrome.

Same issue. I am loged in the Bizagi portal and thus should have access rights.