Sorry but I am extremely busy in setting up an online Bible School. It is quite a lot of work: Revealed Word Bible College
Anyway, the dream is a reflection of how people feel and how they experience end-times doctrines. Believe me, it is quite complex and that is what every little detail of your description of the box reveals.
The second part of the dream reveals the same thing. The ceiling speaks of something higher than usual, and again it is clear that it needs to be cleansed (washing of the ceiling). This is similar to the dream about the dishwasher. We need to be willing and obedient vessels (like the plastic container being placed upside-down in the dishwasher. If it was upright, the dishwasher cannot wash the dirt (old food or wrong doctrines) out of the container. We are the containers in the dishwashers and we need to be upside-down so that the old doctrines flow out when the water (Holy Spirit) washes the old doctrines out of our hearts and minds).
The ceiling speaks of a blockage or a barrier we cannot cross or bypass because of wrong doctrines (end-times doctrines). The stairs speak of an effort that is necessary if we really want to understand end-time doctrines (See the meaning of “stairs” in the dictionary). It takes a willingness to put in an effort to study the Scriptures that deal with the end times. It also takes a willingness to accept what the Holy Spirit will reveal to us when we want to know the truth about the end times. It takes an open mind that is willing to understand and accept the truth about the end times. Believe me, it is not easy and many pastors nowadays choose to rather ignore this subject.