Normally when you are on the registration detail page, the checkboxes are behind the r-events.
If you want the checkboxes in front of the r-events, you have to go to: 1.reg.items > 2.item settings > 3.extra settings.
On the extra settings page, you have the possibility to show the checkbox/pulldown in the front of the text.
Click on the checkbox and save settings.
The checkbox in front of the text.