90 300E Transmission Leaking

[Bill '90 300E]

Hey guys. I recently had my transmission serviced (filter, gasket & fluid). The gasket was a Mercedes part and the pan was supposedly torqued to MB specs. The trans shifted well as I drove the car home (approx. 5 miles) and then I parked it overnight. I was heading out today and when I put it in Drive, I immediately noticed a "flaring". I put it in reverse, backed up and parked it. I then noticed a fresh stain/puddle of tranny fluid. I spoke with the shop owner and he wants me to have it towed to his place on Monday morning. The service was done by a master tech (but not a MB guy) with 30 yrs. experience. Any suggestions (other than the obvious) as to why this may have happened? Do the tranny bolts need to be re-torqued after it has been warmed up and driven? Any help is appreciated. Thanks in advance...