The smaller door and frame can be downloaded here - https://www.dropbox.com/s/zvyoxuje6dcofwu/single%20door%20and%20frame.zip?dl=0 . A few things need to be noted - the frame is standard size (in order to fit in with the rest of the models), but the door and doorway are half size. For some reason, the g_Entity[e]['plrvisible'] command (used in the door.lua script) would not register as 1 (ie visible to the player) when the door is placed perfectly in the doorway (if I offset it slightly it would register as visible, but not in its perfect position). I couldn't figure out why this would be the case, so I changed the door.lua script (included in the zip file as door_small.lua) to remove the relevance of player visibility.
Placing a ceiling section above the door frame can be tricky, as the vertical snap function doesn't work here. Rather than using f9 edit mode or free flight mode (they are still not great for precise positioning), you can add a floor_wall segment somewhere in the scene, move the ceiling segment over the wall, hit enter to snap the ceiling to the correct height, then hit page down once, page up once, and it should be and stay at the correct height.
