in reply to Help, pls, w/ CiviCRM::Client::REST->login() failures . . .

Thats funny, I would add
$self->{_ua}->add_handler("request_send", sub { shift->dump; return } +); $self->{_ua}->add_handler("response_done", sub { shift->dump; return } +);
And I would try to make it work with the demo site