Overall the mod has some major flaws. The first of which being that you need to add a <KEY command, or a <PRI command before you have messages. These commands are both used to lock the player's input so that you can't move around while text is being shown in a message. The next issue I saw was from the text box in question. The text in it wrapped down to the next level of the message box before a word was finished. This is solved by pressing enter in the code directly before the word that wraps down to the next level of the message box.
Next: you need to add a <TRA command between each of your rooms to make sure that transitions between each room are smooth and fluid. Finally, in the sand zone-esque room, there is a lot of inconsistent tiling. It's best to make sure that there aren't sudden jags in your tiles. The tiling in said room is very... flat, too. Try to have a bit more variety with your tiling.
Hope this helps. :'*N