Steve replied:

Roger: travelled this one in 1998. Its no worries, and in some parts really good. There are about 20 creek crossings and you need a permit to travel from the Northern Lands Council in Katherine-- you must get this before you go and apply as soon as you can!! A couple of months before you go at least !! There is no camping permitted on Aboriginal Land areas at Nhulunbuy and special permission needed to camp at the beach areas.
Recommend you do a thorough check before you leave and be mindful that things take time.
The creeks are not big rivers but obviously in flood are not passable, it is a well used road and can be covered in one day albeit a longish one!

Steve