My fix was to make it easier to use. It is more difficult from a developing perspective, but for someone who just grabs the widget and wants it to work, well, the only values that you can edit without clicking 'New' are the ones that appear the moment you click over to the apt menu in the properties. The values you edit remain named. This was intended to make it a bit more user-friendly.
Attached I have put a new version with the events named. Although not my intention at the start, this might be even better than my original plan. The values not to be edited remain at the bottom.