-"...now beginning to buckle under the increasing weight...." Why is the weight increasing? Who/what is adding to it as they go?
-Where you talk about the "warning" in the unnamed girl's eyes, I suggest putting that in italics rather than quotations. If you prefer quotations, however, be sure it's consistent; at the moment, you have a quotation mark at the start and an apostrophe at the end.
-"...witness the full curiosity of her." I'm not sure you mean curiosity here. "Mystery" maybe?
-"Despite her air...more like a doll." This sentence is really choppy with all of the clauses. I suggest rearranging it so that it has less commas. Maybe something like, "Despite the regal air which made her seem large and imposing, she was rather small in size. With her neatly plaited white-ginger hair and lacy moss-green dress, she appeared more like a doll." It's always a good idea to avoid using the word "big". There is almost always a better, more specific word for that, such as "large" or "huge".
-"Ahead....old streets." This paragraph is one giant run-on sentence. You need to break it up into smaller ones.
-Your characters aren't consistent. I especially noticed this in the second chapter early on, when Yxalle is talking about the dress, he suddenly switches to really proper english in stark contrast to his dialect in the chapter before. Just be sure to keep it consistent.
-I would recommend splitting up the monologues by one character. Often times, you use dialogue to just spit out a bunch of facts, but that can sometimes be cumbersome for the reader, and they don't take it in as well. For example, instead of having Yxalle just rattle off a bunch of information about the layout of the palace, you could make it more of a back and forth like:
"...According to our investigations, the king's bedroom and storage room where the slates are kept should be in the center of the highest floor."
"Okay, and what about the sons' bedrooms?" Syla asked.
"Various areas on the floor below."
It just helps make the dialogue more realistic.
All in all though, it's pretty good so far, and intriguing. Keep it up and good luck in the competition!
I think that's about it.