Hi there, i have 1996 E36 318i that is giving me the same problem as your325i. in the morning, or when the weather is cold, the gearbox warning light comes on. When the light comes on, the gear box goes in to fail safe mode that is when only the 3rd and 4th gear can be used. But when the light goes off during hot weather under direct sunlight, the gearbox works fine. All gears work smoothly and i have been told by BMW mechanics that my gearbox is in mint condition as gear shifts are very smooth with no indication of gear slips. But the odd part is when the gearbox warning light comes on, the modic(launch) cant seem to even detect the gearbox. But at the same time, when the light goes off the modic is able to detect the gearbox and it shows that there are no fault codes. This is always the case. I have so far changed the gearbox oil and filter, all solenoids have been replaced, gear shift wiring has been checked. The only thing that is left is the EGS(computer control unit for the gearbox). Im almost sure that the problem with my car is not because of the gearbox but that of the EGS unit. I have once tried to remove the EGS in the morning,before starting the car and applied direct heat on the EGS unit with a hair dryer. I plugged the EGS back and it worked fine as the light did not appear even when the weather outside was cold. So i strongly feel that u need to get your EGS unit checked out also. Plese feel free to contact me if u have any questions regarding your car, i know how stressful and costly it can be to have this problem. I have yet to replace my EGS unit as it will cost me between RM1000-RM1300. Anyways, i would like to advise you to be cautious of mechanics that go by the principle of "try and see lah!!!"...this would prove to be very costly as i have already experienced this very expensive lesson. So do keep me updated. Cheers mate!!