New radio - steering wheel controls advice pls.

Hi, my Columbus stereo went German. I was never happy with it so I decided to fit a new head unit with wireless Apple CarPlay. I bought a Kenwood and the Connect 2 connections to adapt the wiring. This included the steering wheel control. Initially there was no sound but I disconnected the car battery for half an hour which apparently bypassed the Canbus(no idea what this means but it worked). Everything now works apart from the steering wheel controls. The programming options in the new HU are greyed out. I went to the Connect2 website and they specified an order of installation- connect to the radio first and then to the car loom. This made no difference. The new loom is connected to the HU with a 3.5mm plug which is labeled as the SW control. There are also 2 wires marked sw1 and sw2( at least I think that’s what they are, the HU is currently installed). There is also a GND wire which makes no difference if it connected or not. I’ve left it unconnected. I’ve also read that it may be necessary to cut wires on the connect2 loom and even wire something into the car loom.

I’m stuck for ideas. Advice would be appreciated. Thanks.