Hrqls: Yes, you set the playing strength at Settings/Players. Just click on expert and select World Class. You can do this for both chequer play and cube decisions. Then do the same under Settings/Analysis and Settings/Evaluation. Experiment a bit if you like and when you're happy click on Settings/Save settings. Otherwise next time you run it, you'll be back where you started.

1-ply is a compromise between speed and ability. Just don't trust it too much.