Workflows and the SharePoint services required to run them refers to older versions of Nintex Workflow that are 2 years old (NWF 2010 version 18.104.22.168 released on 12/2/2014 and NWF 2013 version 22.214.171.124 released on 12/2/2014)
Nintex Workflow System Requirements This should be checked for accuracy as the communications around the versions do not include current status. Like newly supported versions of SQL, browsers, and SharePoint 2016. The contact information at the end may need updated or appended to also. Logos are not current. Doesn't include Hawkeye.
How to get permission for Product Downloads Not the only way you can gain access to the product download area. Doesn't cover newer licensing model. The included discussion could be updated also if you don't want only support tickets.