Odd state driving laws

My wife was in the service & stationed in Maryland but we were allowed to keep our cars tagged in our home state (at the time) of Kansas. I took my car in for an alignment & they made notations about body rust & the fact that the door panel on the driver's door wasn't fastened all of the way around. I got the impression these were safety violations for Maryland. This was in the mid 1990's. I remember somebody telling me that rust holes would cause a car to fail an inspection & that it didn't matter how you filled them. They said just fill them with bondo, as long as the holes were filled.