Built to keep rabbits safe in the garden, a hutch is usually a little shelter in a mesh run. The size of the actual droppings will vary with the size of the rabbit, but if the size of the droppings changes suddenly and become small and hard, this indicates that the rabbit may have the beginning of gut stasis, a serious condition that is often fatal (see second photo below, showing normal droppings compared to those from a rabbit suffering from gut stasis in the latter stages before it stopped passing droppings completely).
For the roof, make a grid of 3 panels by 2 panels the same way you did the floor, and attach that to the top of the panels, except for the door.Alternately, if you run out of panels, you can use a piece of fabric or an old bed sheet to cover the you have a particularly unadventurous or short bunny, you can leave it open, but even the laziest bunny may try to climb out if really bored.
You can increase the chances of the rabbit moving around more by providing access to exercise at all times and giving items like wicker baskets, cardboard boxes, tubes and other items to stimulate interest, and if the rabbit is on its own it is worth considering doing a match-up as rabbits often take more exercise if living with a compatible partner.
Detailed information on how much to feed and what to feed is in the feeding section of this article, but basically the general rule for an average sized adult rabbit is one flat egg cup of pellets per day per rabbit, lots of fresh hay, and green vegetables that the rabbit will tolerate, starting gradually with something like celery if bunny is not used to having fresh food.
Often the signs that the disease is present only show when the rabbit is stressed in some way or has some other health issue develop in addition to it. Sadly, chronic pasteurella is not curable as such, but can often be managed by giving antibiotics for a period of time when it flares up. Sometimes the condition can be fatal by developing into pneumonia, from which a rabbit rarely recovers.