In the Wheel Editor ...
>> Saving your changes
1.Click on Actions.
2.Click on Save.
OR just press 
S
>> Creating a new Wheel Design
1.Click on Actions.
2.Click on Save Wheel As.
3.Enter a name for the new wheel.
4.Click on the Save As button in the bottom right.
This is how to copy an existing wheel after changing it first, or without changing it at all - either way you take an existing wheel design and save it as a new wheel design.
>> Deleting a Wheel Design
1.Click on Actions.
2.Click on Delete Wheel.
3.Click on the wheel you want to delete.
4.Click on the Delete button in the bottom right.
