There is a trick to seating the mechatronic sleeve that I just learned the hard way. Unfortunately you will have to drop the pan again. When setting the latch on the mechatronic that holds the sleeve, you have to push the sleeve into the transmission while engaging the locking latch. I had intermittent errors and stuff for a year after I did mine. A few weeks ago I dropped the pan and this time I used a pry bar to push the sleeve in a bit more. I actually did this with the connector plugged in and screwed down. It's a bit of a trick because you can push it too far and it won't latch. I pressed mine in then slowly released the pressure until the latch locked. I measured it and was just under 3mm. It had been almost 5mm before. Very smooth operation since.
Hobby mechanic doing my own work for 50 years or so.
We have a 2006 530xi Touring and a 2008 535xi sedan.
I can't really remember the last time I took a car to a repair service.