You could try another browser or try making a backup using eBuddy to see if the password works. It should be resetting if you’re getting to the blinking red light on the reset. Make sure that you’re disconnecting power for at least 10 seconds after the reset process completes.
As far as the second level reset, the Cosy setup is very simple, so if you know the IP address it should use, the SSID and password if you’re using WiFi, and have access to the Talk2M (ecatcher) account, you should be able to reconfigure it. You would only have to change other settings under certain circumstances, like if someone had to access LAN devices from the WAN network, or if the LAN devices needed internet access, for example. If you’re just using it for basic remote access, there are only a few settings to configure.