Thanks for letting me know, I've emailed you some firmware files and a guide that should help you get the AP updated enough to use in HiveManager.
Configuring the APs via the CLI is tricky for a few reasons. Mainly, most configuration commands get erased or reset when an AP reboots if there is no configuration in the running config to save those changes permanently. We can typically get around this with a supplemental CLI object, but that comes through the HiveManager so you'd be subject to the HiveManagers limitations anyway. Also, Connect will be able to recognize features that are enabled on the device but not supported in Connect, and it will disable those features. So you'd have to avoid any configuration update from the HiveManager and any reboots of the AP, or you'd have to rebuild the CLI configuration all over again. Finally, CLI configuration isn't supported by our technical support team, so if you ran in to issues and wanted to open a case for this, they wouldn't be able to help you. So overall it's possible, but on a temporary basis more than a permanent set up option.
