Yes, you can switch back to the energy efficiency mode / please sleep with the Timer after the download!
1. If, however, a download is running, switch to "Please don't sleep"
here in the example of the Windows server download for about 6 minutes on Chrome!
2. And set the timer to, for example, 15 minutes to ensure that the download is made.
3. Then the tool switches back to "Please sleep" mode ;-)
Turn Computer off, reboot, log off, hibernate or standby and disable the prevent feature in Dont Sleep When you click one of the options via To-Tray menu
It is pretty easy to use start parameter e.g. program arguments in Dont Sleep for example to use for launch via batch file Content / Solution / Tip: 1.