Hello,
if possible we strongly recommend using the ACC V2.1 BETA with the latest (soft-released) AxG 7.501. This will allow you to use all new features of ACC, including the Aggregated Reporting capabilities.
There is support for all other features besides Aggregated Reporting within AxG 7.500, but there might be one or two minor flaws.
Of course your previous installations of AxG V7.3 and V7.4 will continue to work with their respective feature scope in ACC V2.1 (e.g. Monitoring in V7.3, VPN configuration in 7.4). The new configuration and reporting features require 7.50x though.
Hope that clarifies things a bit.
Regards,
Henning