Here’s a DCT trans in a 135i,,,,that I found leaking from the side cover,,,the last pic is the transmission removed and the side cover removed,,,,under the side cover is the mechtronic valve body,,,,on all the other ZF trans the mechtronic valve body is located under the lower trans pan gasket,,,,but since this is a GETRAG trans it’s built a little different,,,,,this job you can not do at home,,,,,unless you have a lift to drop the trans,,,,,there are some rumors you can do it in the car,,,,but I won’t chance it,,,,to easy to screw up the gasket when putting it back together.