GIESSE - as stated, your fields are not setup correctly, which is why your auto-selected value is happening. Your selection limits is not right and the selected values is also not right. Please watch this video tutorial to see how selection fields are properly setup. It's an old video, but it will still apply. Once you fix the field, you may have to re-save the event to get things all working correctly.
rjeffl - if your conditional fields are not being activated, then you didn't follow the instructions in the 2.8.12 release announcement. New ability to control conditional fields was added, which required you to open each event that uses conditionals, and re-save it. Go to the fields tab, click the new link to toggle display of conditional fields, and make sure your conditional fields are enabled for the event. Yours clearly are not enabled. Has nothing to do with your selection field or CSS.
brwalker (and anyone still having this issue on the backend) - go to this file:
/administrator/components/com_dtregister/assets/css/admin.dtregister.css
Find ".dt_checkbox_label" and change the styling to this:
.dt_checkbox_label {
padding: 0 10px 0 5px;
margin: 0 0 0 15px;
}
We'll apply this for the next package update.