OK, here's an explanation of the entire poem. Sorry about its length.
"You wake up in a maze of confusion"
Most people's lives are a maze of confusion in many ways. Especially before they come to Christ, which is the situation that is described in the early part of this poem.
"Stone tablets form its imposing walls"
Stone tablets is a kind of reference to the law of God. Here it is a kind of vague and veiled recognition that the evil (sin) in us is what keeps us from being in the state where we wish to be.
"Earthquake adds fear to heart's fusion"
An earthquake is a destructive force. Here it represents all kinds of reminders of the finitude of life, the fact of death, etc. When we realize these to a greater extent, it can cause fear (also see the explanation for "heart's fusion" in an earlier comment).
"Desperately seeking an exit before it falls"
"It" means the maze that was mentioned a few lines earlier. This is the urgency to find the solution given that we only have limited time.
"Every moment it becomes smaller
Yet its dimensions stay the same"
"It" still refers to the maze. So this just means an increasing sense of anxiety about one's situation.
"Menacing shadows grow taller
As soul's nakedness meets its shame"
This also has to do with anxiety, but perhaps more of an internal kind where one recognizes his/her own sinfulness and the truth about its extent. Kind of like a fuller awareness of the law without having truly known and believed the gospel yet.
"When the night falls in this maze
They finally arrive to haunt you
Beings of dark light ablaze"
Kind of a reflection on Jesus' words in Matthew 6: "So if the light that is in you is darkness, how great is the darkness!"
"Taking your own form to taunt you"
Sometimes it's not clear how much of the forces of evil are internal (our fallen nature and self-chosen patterns of sin) or external (demonic/satanic). Sometimes it can be a combination. So here the beings that come to haunt the person do in some sense seem to be external, and yet they take the form of this person (in other words, they look like him/her), perhaps symbolizing a moment realization that not all of the evil is from the outside, and so one can't just shift blame with "the devil made me do it" (or even "others made me do it") type of thinking.
"The feeling of helplessness
The shaking that follows
Silent gasps of breathlessness
Echoing the empty hollows"
This is the result of everything that has happened so far. It highlights the hopelessness of the human situation when we are on our own, not relying on God.
"No way out from the edges
So you head toward the center"
A relization that you can't escape your predicament on your own. You can't find an exit from the edges of the maze, so you are trapped. Heading toward the center is a change of direction.
"You see a crowd outside a narrow gate
Where only a pure heart could enter"
You realize that there are others dealing with the same issue and seeking a solution. A narrow gate has its Biblical connotations, and the requirement of having a pure heart as a condition for entry highlights the problem of human sinfulness. People are gathered on the outside because they can't enter.
"The place where width and height meet
To mourn death and celebrate its loss
Ground feels the weight of eternity's feet
Where frailty and heavenly power cross"
In this whole section I tried to give hints about the cross of Christ as the solution without saying it directly. The last three words are literally "heavenly power cross" but of course the word "cross" his here a verb describing the "crossing" (of frailty and heavenly power) and not a noun, so it's still kind of a veiled reference.
"Place where width and height meet". Think of horizontal and vertical lines intersecting each other. They form a cross. That's one clue. But also, one could think of the horizontal (width) as a symbol for earthly matters and the human domain, our relationships with each other, etc. The vertical (height) would symbolize the relationship between God and humans. So the horizontal and the vertical meet at the cross when Jesus as both God and man came to die for our sins and provide the solution ultimately for both the horizontal and the vertical domain. Frailty and heavenly power cross each other as the Son took a human nature and so his human body was subject to death on the cross, yet it was the power of God that was at work in all of this. (Think Philippians 2:5-11, Romans 1:16, also echoes of 2 Corinthians 12:9). This is the solution to what we could not solve on our own. Christ was the one with pure heart that could make it possible on our behalf.
"To mourn death and celebrate is loss" seems kind of paradoxical, but it can make sense in the context of Christ's atoning death. First of all, there is a sense in which it is sad that Christ had to suffer and die, even though it's the greatest news ever. And also "mourning death" is the normal human sentiment in general. What's "celebrating its loss"? Well, it turns out that it's death itself that suffered the loss here as Jesus through his death redeemed us from the power of sin and death. So we get to celebrate that death lost its grip on us!
"Ground feels the weight of eternity's feet" describes the fact that God himself is present in this event. It's a way to talk about God having become human in Jesus. When Jesus walked the earth, he was God walking among us.
"You sigh and wait for hope
Then hope in the faith you found
Ears opened for your heart to see"
Having now come to see the cross, there is a yearning for hope, and the hope is found through faith. "Ears opened for your heart to see" is a reference to the concept of "Faith comes by hearing" (Romans 10:17).
"When the beast has been bound
And the slave delights to run free"
This is the result of salvation. We used to be slaves to sin but have been set free by Christ.
"You build your trust to bow
Thirsting for the day you know
That it truly is finished"
This describes how Christian life still continues with its own difficulties. There can be issues with trusting God, doubts, etc., and also thirsting for fuller knowledge (echoes of 1 Corinthians 13:23). "You know... that it truly is finished" means full reliance and trust in the finished work of Christ. Perhaps moments of confidence that God may already provide for us here, but ultimately the knowledge of it that will come after this temporal life in its fullness.