I also have an N62 X5 and firstly can tell you that I’ve always had the steering angle sensor and braking force codes, they seem to be fairly common and have no impact on my motor.

Secondly I have an NT510 scanner but nothing is better than INPA/ISTA and an OBD/USB cable, will also only set you back about $20.

I did rebuild on my engine about 3 years ago and at the time also replaced Vanos solenoids, I figured if I was replacing everything else I might as well and a few YT vids and guides had said it does help with a rough idle/cold engine idle etc. This may help but you also, may have an issue with your camshaft position sensor, I remember the connectors on these being really easy to snap when replacing rocker cover. They are located at the back of the head near the bulkhead the part number is 12147518628 if you’re looking for some diagrams then this is a great resource https://bimmercat.com/bmw/en/search/...is/ECE/11_3821

The other thing to possibly check is that the VANOS control unit is In good order, this is in the control box under the bonnet near the windshield, the modules in here including the ICM can get weathered and damaged, I had this with my IC module. The other things that a lot of Indy BMW techs will tell you is that the OE Vanos solenoids are actually quite poor quality and you should replace with something other than the BMW brand ones, Pierburg often comes up as a recommended brand. Hope you get it resolved, once you do the best advice I can also give is to get an EVC, I got one from SAAS and it’s just a different beast without the throttle input lag!