Hello
i have the same problem with newer firmware as 4.5.16.
Today i flash new newest beta firmware v4.7.4 ans reset it to the default config.
When i import my VPN config from the AVM FritzBox the connection succesful established. But only the local device in the remote network have access.
Here my configuration
[Interface]
PrivateKey = xxxxxxxx
Address = 192.168.26.1/24
DNS = 192.168.167.1
DNS = fritz.box
[Peer]
PublicKey = xxxx
PresharedKey =xxxxx
AllowedIPs = 0.0.0.0/0,::/0
Endpoint = xxxxx.myfritz.net:54924
PersistentKeepalive = 25