The evaluation buttons on https://agentpp.com/download.html work, I just tested it. What browser are you using? Maybe there was just a networking issue?
The evaluation request email has been received but not processed yet.
An AGENTPP site license covers all users working at the licensed site and all telecommuters reporting to managers working a that licensed site (site = business location with a unique postal address).
This particularly applies to AgenPro, MIB Explorer Pro, and MIB Designer.
For SNMP4J-AgentX, SNMP4J-SMI-PRO, AgentX++ the statement above is true too, but the license differs a bit from the tool licenses because the latter are development licenses. The distribution of the APIs in binary form and bundled with a value-adding application is not bound to the users nor a specific site with those licenses.
The developers, build managers, i.e. anyone using the API code (binary or source), however, is only allowed to use those APIs if he/she is working at the licensed site (=location) or - as a telecommuter reports to managers at the licensed site.