Flexget

At first use you must set a new password for flexget using the command line:

sudo su -s /bin/bash sc-flexget -c '/var/packages/flexget/target/env/bin/flexget -c /var/packages/flexget/var/config.yml web passwd <MyPasswd>'

Using your browser at http://<mySynoNASIP>:8290 and login as user flexget with your newly associated password.

From there follow https://flexget.com/Configuration to complete your configuration.