Note: The Controls on the far left in the black navigation bar above can enable a reference image of the completed puzzle as well as a ghost image of it on the workspace. You can switch these on or off. If you use the completed puzzle image, be sure there are no puzzle pieces hidden under it. You can also click on the far right button in the bar to play in Full Screen mode, which is recommended. Enjoy!
This one below has 100 pieces so grab a cup of coffee and get comfortable!