arm development studio remote connection via ssh and key

cannot specify ssh key for remote system .

it fails to connect with authentication failed.

in remote  systems i create a

new-connection -> ssh only -> (provide host name etc)

when i try to connect it fails. with authentication failed. expectedly , as it does not know where the ssh key is

in preferences->network->ssh2->keys i have specified the key location, but that does not seem to work