Yes, it should use subscribers.conf. And I dont know if it's a typo or not, but make sure the file is named subscribers.conf, not subscriber.conf.
First, the regexp ^001 will never match your IMSI (log says that the IMSI of the phone trying to register starts with 510).
As for the regexp that would match everything ( .*) , make sure you're loading the configuration correctly.
You can check from where yate is loading subscribers.conf by typing status engine in the rmanager console and looking at the configpath variable. Check that you have subscribers.conf in that path, or that the path corresponds to the folder where you've make all your configuration changes.