This sounds exactly like an issue I was having recently. Doors will open, but they don't fully close.
Here's what I found on mine. Remove the upper playfield. Turn it over and look at the return springs on the doors. In the picture below, you can see how the return spring has rotated and is now touching the door latch. This prevents the door from fully closing.
woz_door_spring.jpg
Here's a closer look.
woz_spring_closeup.jpg
The solution for me was to unhook the spring from the opposite end, rotate it once clockwise (for the left door) and to re-attach the spring. This forces the spring to rotate away from the door latch at the other end.
woz_spring_rotate.jpg
St. Clair Shores, MI
