Valvetronic error

[Bob Basket]

Hi,

I recently bought an X1 2010, and it is a really lovely ride and the first BMW for me. After spending time looking for oil dipstick etc, I got used to driving the BMW.

Recently I got the orange engine light on, and with car scanner I got errors P1062 and 28B4, which both indicate something is wrong with the valvetronic motor.

After resetting the errors the car is driving fine again no misfiring or strange noises, and fuel efficiency is really good. However, I do want to fix the problem, and my first question is did anybody DIY this problem? I looked online, and it does not look that difficult (I am reasonably handy).
Second question can you use an after market valvetronic motor? they are significantly cheaper then OEM but they need to be reliable.

Any help much appreciated.

Thanks,
Bob