Aurora R11, water cooling HELP

hi guys new here and only just got my R11, first things first. it was second hand and had the GPU removed and was picked up for £500. my pc goal was always to get an alienware unit but never had the spare funds (kids spent it before i could) i placed my 3070 in to the unit and did a reboot but boy was this beast loud. did a bit of hunting on here and found people had switched the air cooler to a corsair h60. i did this and CPU fan error and cant clear it on start up. i did not like sitting waiting for this to clear so did some more research and found out dell use asetec coolers. found a second hand/new not fitted one on line just installed it and still the same error....... even if i hook up to the cpu plug it still does it. help i need if anyone would be so kind. (i have ordered a VRM heat sink but its coming from the states) 

1: is there any way of turning of pre-boot checking.

2: why does the system not recognise ether of the water coolers. 

3: changed Case fans to corsair ML120 but system does not like them and gives the same error as CPU fan not responding correctly.

4: can you buy the stock cooler from dell (cant find it)

thanks in advance