is there any way to change the order of tasks on the due list for a given day?
The order of the tasks on the due page for a given date is defined by the order of the lists where those tasks appear, and by the hierarchical order of those tasks within the list.
I.e. the first task in the list with the given due will appear first. Lists are ordered alphabetically when sorting.
So if you want to make task appear at the beginning, you should place it in the beginning of the list, and rename the list so it appears in to be alphabetically higher.
Hope this helps,