SSH Quick Connect (AWS Account) stops to working

I'm using version 4.5.3.0 (Windows).

I'm using an "Amazon AWS Console", to list my instances.
In Windows instances, quick connect works correctly, opening a RDP session. But with a Linux instance, RDM open a window (Connection Settings), to confirm the DNS. After it opens another window (Amazon Quick Connect) showing the host and the correctly user. So I choose the private key file, hit OK: RDM shows a new window: to type the username (Again??????) If I cancel the window OR type the username again, RDM closes the window, or hangs.

If I click on "create connection", specifying the same private key file, it works.

My private key doesn't have a passfrase.

I've tried to use a ppk file, a pem file.