The auto-advertise message feature will only work when the interface is showing. If you hide the interface, the auto-advertising stops.
The player must edit the generated message after they have adjust any of the role quantities or changed a drop down menu item otherwise the customized message will be replaced with a new auto generated message.
There are no restrictions placed upon player as to the desired interval entered into the "Auto-Advertise Interval" editbox, allowing for the possibility for this feature to be abused by spamming a message in as little as every 1 second.