Well after I got a email back from Asus last night stating I had to go through the the RMA of who I brought it from, who was the damn ASUS store direct! I even gave them the order number.
I thought I would have a go at just stripping the system down and starting again. So this time I went a single component at a time, so inserted the CPU and switch it on (on/off switch on the MOBO is a game changer), successful boot to missing RAM error code. So I then went to insert the water block back plate, the contact frame, the RAM, each time I was switching it on to ensure a correct error code.
Until the entire system was back, I cant explain how relieved I was to at least get this far and it seem to be working okay. Next I went thought I would just check I could get into the Bios okay, so plugged a monitor in and booted...... No display, VGA error.... So again stripped this out and then tried without the riser cable and strimmer power cable, straight boot all green lights. Then I tried with the riser cable and all fine, then I plugged in the strimmer extension, No display..... So it was something with the strimmer extension, reading around I found that it seems to be the sensor cable pins can work out slightly, so after a lot of playing with the cable connections, BOOM! display to bios.
Therefore I have finished up the pipework and this is no on pressure test for a hour to check all okay, then ill get the wiring sorted and start a fill. Then final jobs of cleaning up, wiping all chrome, also fixing the pump grommet in place as I now know where I like the cable to route.