Hi Rixu,
Looks like this is general question about Little Math. You have posted this in the wrong section, it belongs in the Little Math General Discussions board.
I will be moving this post for you to the appropriate thread.
As for your issue, please choose the icon set you want by going to the PLAYBACK Menu, an clicking on SETTINGS in the Display Settings Panel.
In the Icon section, drop down the menu for the ICONSET. You should find what you are looking for there.