When I first got my MKII the same problem happened.

The door glass was not dropping
The interior light was on most of the time
The battery was always going flat as a result (original one still installed)

However I also had some marks (almost deep enough to be called a gouge in the edge of the door frame) just below the lock/catch assembly.

The door had dropped slightly on its hinges as I assume the previous owner had been leaning on it (bad bad bad dog) to get in and out. This put it out of alignment causing it catch on the shiny metal edge trim. As a result it did not close correctly and the light never went on as the switch did not engage.

Millers said that it took a couple of goes to get the correct trim peice as the MkII was a bit of a wedge from the MkI to the MKIII in this respect and so got a number of on the go changes.

Once the door adjustment was made, the trim replaced and the reset performed this did clear it and it started to work well.

To test this I did the following

Take down the lid and use the light to indicate if the door is closed correctly. Close the door and see if it "catches" and look for marks in the frame. Lift the door slightly as you close it to see if it closes more cleanly and the light goes off.

Then try the same with the window lowered into the door and see if it works.

If this works then you need to sort out the trim, frame, aligment and then do the resent.

Certainly if you let the battery run empty with the windows out of kilter then they do not close correctly and a reset is needed. I have had to do this after I replaced the battery a few months ago.

HTH

Everyone loves a Morgan. Even me, unless it's broken again.