Alot of the above code has been nicked/nobbled/adapted from stuff I have researched online, it was just the stitching together I did really, and many hours scoping to get the speed/reliability/throughput as good as I can get it
I have successfully transmitted and received 512 channels over 25ft through 2 solid brick walls at 25hz to give a very smooth result at my collection of DMX fixtures, there was little or no noticable loss of data packets as there is always a good one following up 40ms later !
The nRF24L01 boards I used were the ones with the antenna ON etched as part of the PCB at a cost of under 1GBP a go !