Update
 

Ok.had the car today in to check the brakes, change brake fluid before going to a performance driving session at knockhill (present from son/daughter) and there was a slow leak on rear nearside hose connection to caliper. Just needed tightening up. So that seems to solve the question of where the fluid went.

Glad it was an easy fix mate, and you need to keep an eye on your fluid levels more often. You should know better, dip the tanks!

Guys I’m having the same problems, ABS Light every couple of months, if I hit a pothole. But i get the hickup from the tranny when starting from standstill, it just bangs into first gear let’s say 2-3 times out of 10 starts. What could this possibly be? My brake fluid ist on max, brakes are okay... Why is the tranny acting up? The trans module has 0 errors, and the trans has always been serviced. Other than that it changes gears seamles!

Does the transmission hard shift into 2nd under heavy acceleration?
How's the fuel economy?

I'm thinking MAF.
The ECU and TCU work together to give smooth shifts.
The MAF is vital to the ECU for this as it gives information on engine load and torque based on throttle position and airflow.

When my MAF went I got a very bad shift 1st to 2nd under heavy acceleration.

My money is on 2 separate problems here. The gearbox is quite likely a worn F125 switch. What exact codes are coming up anywhere on a VCDS scan?