Does the Agama app require connections outside the United States to operate correctly?
As far as I know no. Whether you are US resident or no you can enjoy the same GUI functionality as others. However, the recently discovered bug could be due to connectivity issues, namely a fair amount of connections from non-US IPS could trigger some kind of inconsistency in the code and result in what was referred to as bug but there's still the possibility it was a deliberate mistake.