Glad you like it! Your suggestion is already tracked at https://github.com/seansfkelley/synology-download-manager/issues/45 (short version: have to wait for Firefox to support this, unfortunately). As for the second issue, I've seen that before so hopefully it's an easy fix and lands in the next version! For now, you should be able to get around it by logging in with a second account then logging in again with the first account.