Doors

Morbeus makes a point about the doors being functionally shaped for the body structure of the Krell, yet the crew has to crowd into the shuttle transport to go to the power center.
Was there a sub-species of "Krell Technician" that was smaller? a subject race from another planet?
When I saw this as a child I was struck by that seeming mistake, however as I was sitting in back seat of the car going home, I thought perhaps these big pyramidical shaped slugs who were the Krell had enslaved some small-statured intelligent race of technicals who installed all this techy stuff, and kept it running.
It worked for a 7 year old, why not?
Second thing. Even as a child I knew that Robbie's dialog was written by someone who didn't know the jargon. He says he is "Monitored" to admit no one at this hour". A properly written line would have said "Programed". I had been reading sci fi for a year by that time, and know that writers used that word.
I know, It's just a movie, but still.