Check if your door instance is something like this:
(instance aDoor of Door
(properties
y 150
x 150
view 22
entranceTo 10
)
)
then check are the door control colors right. (Navy for the area where player can open the door, yellow for blocking ego to walk trough the doorway unless it's opened and dark green which takes player to the room specified in the door instance.
Then use:
(if(Said('open/door'))
(aDoor:open())
and walk trough the doorway. This should do the trick.
-Eigen