WW 2.12. Using the problem set editor I see that we can change problem ordering by "dragging and dropping".
There is also a "Renumber Problems" button at the top of the set but it doesn't appear to do anything when clicked. Some faculty are asking if there is a way to change a problem's number within a set by entering a number for the problem like in older versions of WW? For example in 2.10 there was a blank box next to each problem number where one could enter new desired problem number.