I think your problem is not directly related to the timing cover leak unless the leak is drenching your driveway. I know that there is a low oil level warning as well as a low oil pressure warning. There could be some sort of problem with the sensor or wiring. If the level is up, the low level sensor should not be on. Pressure you should monitor on your guage, it should be maxed when going down the road and not fall too close to zero at idle.
Long and short of this, check your oil level sensor and circuit first.
'84 Euro 240D, 523K miles
'88 300E 5 Speed
'81 300D Daughter's Car
Over 800,000 miles in