To turn it from a single pray into a shower spray pull the end of the tap down, as others have stated the hose can kink.
As to the shower bracket, the part where the tap fits rotates but is very stiff, I rotated mine by using a plastic awning peg - carefully - as a lever. The bracket on our Ranger 500-5 was the wrong way round and from previous comments in this thread it seems this is quite common.
We have a bailey ranger 500/5 took me nearly a year to figure the tap out to get a spray for shower. Pull the head of the tap down hey presto turns to a spray. Found this out by accident, after puzzling me for months. instructions you get for caravan are not that clear are they?
Mine has been on spray all the time and I didn't realise there was a different setting for the WHB. Oh well, will be able to try it out at the weekend.