1. Make a group of radiobuttons in your plot
2. Drag a single radiobutton to your plot and add it to the group
3. Select the new radiobutton and open its “Behaviour…” dialog
4. Choose “Clicked” and select “Operate on Element”
5. Click on the “Choose…” button
Now, the new radiobutton in the group is not visible. However, the cursor changes on mouse over and if you click where the radiobutton should be, it appears.
In the above example – before adding the new radionbutton to the group – both the group and the single radiobutton has Z-value 0.
The problem gets worse, if the groups has e.g. Z-value 10 and the single radiobutton has Z-value 0, bacause then in the “Please Choose An Element” dialog the new radiobutton can’t be selected at all.